Go: move the stdlib to a different file
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parent
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GPG Key ID:
A0420B94F92B9493
495
ell/ell.go
495
ell/ell.go
@ -20,11 +20,6 @@ import (
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"errors"
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"fmt"
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"io"
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// standard library
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"bytes"
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"os"
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"os/exec"
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)
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// --- Values ------------------------------------------------------------------
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@ -717,493 +712,3 @@ func (ell *Ell) EvalBlock(body []V, args []V) (result []V, ok bool) {
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ell.scopes = ell.scopes[:len(ell.scopes)-1]
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return result, ok
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}
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// --- Standard library --------------------------------------------------------
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// EvalAny evaluates any value and appends to the result.
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func EvalAny(ell *Ell, body *V, arg *V) (result []V, ok bool) {
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if body.Type == VTypeString {
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return []V{*body}, true
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}
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var args []V
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if arg != nil {
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args = append(args, *arg.Clone())
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}
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if res, ok := ell.EvalBlock(body.List, args); ok {
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return res, true
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}
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return nil, false
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}
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// NewNumber creates a new string value containing a number.
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func NewNumber(n float64) *V {
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s := fmt.Sprintf("%f", n)
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i := len(s)
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for i > 0 && s[i-1] == '0' {
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i--
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}
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if s[i-1] == '.' {
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i--
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}
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return NewString(s[:i])
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}
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// Truthy decides whether any value is logically true.
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func Truthy(v *V) bool {
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return v != nil && (len(v.List) > 0 || len(v.String) > 0)
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}
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// NewBoolean creates a new string value copying the boolean's truthiness.
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func NewBoolean(b bool) *V {
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if b {
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return NewString("1")
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}
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return NewString("")
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}
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// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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func fnLocal(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) == 0 || args[0].Type != VTypeList {
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return ell.Errorf("first argument must be a list")
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}
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// Duplicates or non-strings don't really matter to us, user's problem.
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scope := ell.scopes[len(ell.scopes)-1]
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values := args[1:]
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for _, name := range args[0].List {
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if len(values) > 0 {
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scope[name.String] = *values[0].Clone()
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values = values[1:]
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}
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}
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return nil, true
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}
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func fnSet(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) == 0 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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if len(args) > 1 {
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result = []V{*args[1].Clone()}
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ell.Set(args[0].String, &result[0])
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return result, true
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}
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// We return an empty list for a nil value.
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if v := ell.Get(args[0].String); v != nil {
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result = []V{*v.Clone()}
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} else {
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result = []V{*NewList(nil)}
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}
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return result, true
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}
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func fnList(ell *Ell, args []V) (result []V, ok bool) {
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return []V{*NewList(args)}, true
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}
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func fnValues(ell *Ell, args []V) (result []V, ok bool) {
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return args, true
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}
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func fnIf(ell *Ell, args []V) (result []V, ok bool) {
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var cond, body, keyword int
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for cond = 0; ; cond = keyword + 1 {
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if cond >= len(args) {
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return ell.Errorf("missing condition")
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}
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if body = cond + 1; body >= len(args) {
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return ell.Errorf("missing body")
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}
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var res []V
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if res, ok = EvalAny(ell, &args[cond], nil); !ok {
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return nil, false
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}
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if len(res) > 0 && Truthy(&res[0]) {
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return EvalAny(ell, &args[body], nil)
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}
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if keyword = body + 1; keyword >= len(args) {
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break
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}
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if args[keyword].Type != VTypeString {
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return ell.Errorf("expected keyword, got list")
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}
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switch kw := args[keyword].String; kw {
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case "else":
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if body = keyword + 1; body >= len(args) {
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return ell.Errorf("missing body")
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}
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return EvalAny(ell, &args[body], nil)
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case "elif":
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default:
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return ell.Errorf("invalid keyword: %s", kw)
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}
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}
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return nil, true
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}
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func fnMap(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 {
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return ell.Errorf("first argument must be a function")
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}
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if len(args) < 2 || args[0].Type != VTypeList {
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return ell.Errorf("second argument must be a list")
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}
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body, values := &args[0], &args[1]
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for _, v := range values.List {
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res, ok := EvalAny(ell, body, &v)
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if !ok {
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return nil, false
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}
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result = append(result, res...)
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}
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return []V{*NewList(result)}, true
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}
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func fnPrint(ell *Ell, args []V) (result []V, ok bool) {
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for _, arg := range args {
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if arg.Type != VTypeString {
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PrintV(os.Stdout, &arg)
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} else if _, err := os.Stdout.WriteString(arg.String); err != nil {
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return ell.Errorf("write failed: %s", err)
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}
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}
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return nil, true
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}
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func fnCat(ell *Ell, args []V) (result []V, ok bool) {
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buf := bytes.NewBuffer(nil)
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for _, arg := range args {
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if arg.Type != VTypeString {
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PrintV(buf, &arg)
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} else {
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buf.WriteString(arg.String)
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}
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}
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return []V{*NewString(buf.String())}, true
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}
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func fnSystem(ell *Ell, args []V) (result []V, ok bool) {
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var argv []string
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for _, arg := range args {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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argv = append(argv, arg.String)
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}
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if len(argv) == 0 {
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return ell.Errorf("command name required")
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}
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cmd := exec.Command(argv[0], argv[1:]...)
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cmd.Stdin = os.Stdin
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cmd.Stdout = os.Stdout
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cmd.Stderr = os.Stderr
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// Approximation of system(3) return value to match C ell at least a bit.
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if err := cmd.Run(); err == nil {
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return []V{*NewNumber(0)}, true
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} else if _, ok := err.(*exec.Error); ok {
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return ell.Errorf("%s", err)
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} else {
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return []V{*NewNumber(1)}, true
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}
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}
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func fnParse(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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res, err := NewParser([]byte(args[0].String)).Run()
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if err != nil {
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return ell.Errorf("%s", err)
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}
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return []V{*NewList(res)}, true
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}
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func fnTry(ell *Ell, args []V) (result []V, ok bool) {
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var body, handler *V
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if len(args) < 1 {
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return ell.Errorf("first argument must be a function")
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}
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if len(args) < 2 {
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return ell.Errorf("second argument must be a function")
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}
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body, handler = &args[0], &args[1]
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if result, ok = EvalAny(ell, body, nil); ok {
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return
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}
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msg := NewString(ell.Error)
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ell.Error = ""
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return EvalAny(ell, handler, msg)
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}
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func fnThrow(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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return ell.Errorf("%s", args[0].String)
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}
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func fnPlus(ell *Ell, args []V) (result []V, ok bool) {
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res := 0.
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for _, arg := range args {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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var value float64
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if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
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return ell.Errorf("invalid number: %s", arg.String)
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}
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res += value
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}
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return []V{*NewNumber(res)}, true
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}
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func fnMinus(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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var res float64
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if n, _ := fmt.Sscan(args[0].String, &res); n < 1 {
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return ell.Errorf("invalid number: %f", args[0].String)
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}
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if len(args) == 1 {
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res = -res
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}
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for _, arg := range args[1:] {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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var value float64
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if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
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return ell.Errorf("invalid number: %f", arg.String)
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}
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res -= value
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}
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return []V{*NewNumber(res)}, true
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}
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func fnMultiply(ell *Ell, args []V) (result []V, ok bool) {
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res := 1.
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for _, arg := range args {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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var value float64
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if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
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return ell.Errorf("invalid number: %s", arg.String)
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}
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res *= value
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}
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return []V{*NewNumber(res)}, true
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}
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func fnDivide(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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var res float64
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if n, _ := fmt.Sscan(args[0].String, &res); n < 1 {
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return ell.Errorf("invalid number: %f", args[0].String)
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}
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for _, arg := range args[1:] {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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var value float64
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if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
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return ell.Errorf("invalid number: %f", arg.String)
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}
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res /= value
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}
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return []V{*NewNumber(res)}, true
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}
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func fnNot(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 {
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return ell.Errorf("missing argument")
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}
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return []V{*NewBoolean(!Truthy(&args[0]))}, true
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}
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func fnAnd(ell *Ell, args []V) (result []V, ok bool) {
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if args == nil {
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return []V{*NewBoolean(true)}, true
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}
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for _, arg := range args {
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result, ok = EvalAny(ell, &arg, nil)
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if !ok {
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return nil, false
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}
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if len(result) < 1 || !Truthy(&result[0]) {
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return []V{*NewBoolean(false)}, true
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}
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}
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return result, true
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}
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func fnOr(ell *Ell, args []V) (result []V, ok bool) {
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for _, arg := range args {
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result, ok = EvalAny(ell, &arg, nil)
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if !ok {
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return nil, false
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}
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if len(result) > 0 && Truthy(&result[0]) {
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return result, true
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}
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}
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return []V{*NewBoolean(false)}, true
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}
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func fnEq(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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etalon, res := args[0].String, true
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for _, arg := range args[1:] {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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if res = etalon == arg.String; !res {
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break
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}
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}
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return []V{*NewBoolean(res)}, true
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}
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func fnLt(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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etalon, res := args[0].String, true
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for _, arg := range args[1:] {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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if res = etalon < arg.String; !res {
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break
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}
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etalon = arg.String
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}
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return []V{*NewBoolean(res)}, true
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}
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func fnEquals(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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var first, second float64
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if n, _ := fmt.Sscan(args[0].String, &first); n < 1 {
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return ell.Errorf("invalid number: %f", args[0].String)
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}
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res := true
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for _, arg := range args[1:] {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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if n, _ := fmt.Sscan(arg.String, &second); n < 1 {
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return ell.Errorf("invalid number: %f", arg.String)
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}
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if res = first == second; !res {
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break
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}
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first = second
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}
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return []V{*NewBoolean(res)}, true
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}
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func fnLess(ell *Ell, args []V) (result []V, ok bool) {
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if len(args) < 1 || args[0].Type != VTypeString {
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return ell.Errorf("first argument must be string")
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}
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var first, second float64
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if n, _ := fmt.Sscan(args[0].String, &first); n < 1 {
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return ell.Errorf("invalid number: %f", args[0].String)
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}
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res := true
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for _, arg := range args[1:] {
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if arg.Type != VTypeString {
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return ell.Errorf("arguments must be strings")
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}
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if n, _ := fmt.Sscan(arg.String, &second); n < 1 {
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return ell.Errorf("invalid number: %f", arg.String)
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}
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if res = first < second; !res {
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break
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}
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first = second
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}
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return []V{*NewBoolean(res)}, true
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}
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// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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var stdNative = map[string]Handler{
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"local": fnLocal,
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"set": fnSet,
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"list": fnList,
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"values": fnValues,
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"if": fnIf,
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"map": fnMap,
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"print": fnPrint,
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"..": fnCat,
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"system": fnSystem,
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"parse": fnParse,
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"try": fnTry,
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"throw": fnThrow,
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"+": fnPlus,
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"-": fnMinus,
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"*": fnMultiply,
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"/": fnDivide,
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"not": fnNot,
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"and": fnAnd,
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"or": fnOr,
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"eq?": fnEq,
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"lt?": fnLt,
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"=": fnEquals,
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"<": fnLess,
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}
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var stdComposed = `
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set unless { if (not (@1)) @2 }
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set filter { local [_body _list] @1 @2;
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map { if (@_body @1) { @1 } } @_list }
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set for { local [_list _body] @1 @2;
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try { map { @_body @1 } @_list } { if (ne? @1 _break) { throw @1 } } }
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|
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set break { throw _break }
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|
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# TODO: we should be able to apply them to all arguments
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set ne? { not (eq? @1 @2) }; set le? { ge? @2 @1 }
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set ge? { not (lt? @1 @2) }; set gt? { lt? @2 @1 }
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set <> { not (= @1 @2) }; set <= { >= @2 @1 }
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set >= { not (< @1 @2) }; set > { < @2 @1 }`
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|
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// StdInitialize initializes the ell standard library.
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func StdInitialize(ell *Ell) bool {
|
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for name, handler := range stdNative {
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||||
ell.Native[name] = handler
|
||||
}
|
||||
|
||||
p := NewParser([]byte(stdComposed))
|
||||
program, err := p.Run()
|
||||
if err != nil {
|
||||
return false
|
||||
}
|
||||
|
||||
_, ok := ell.EvalBlock(program, nil)
|
||||
return ok
|
||||
}
|
||||
|
||||
513
ell/stdlib.go
Normal file
513
ell/stdlib.go
Normal file
@ -0,0 +1,513 @@
|
||||
//
|
||||
// Copyright (c) 2018, Přemysl Janouch <p@janouch.name>
|
||||
//
|
||||
// Permission to use, copy, modify, and/or distribute this software for any
|
||||
// purpose with or without fee is hereby granted.
|
||||
//
|
||||
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
||||
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
||||
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
|
||||
// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
||||
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
|
||||
// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
|
||||
// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
||||
//
|
||||
|
||||
package ell
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"os"
|
||||
"os/exec"
|
||||
)
|
||||
|
||||
// --- Standard library --------------------------------------------------------
|
||||
|
||||
// EvalAny evaluates any value and appends to the result.
|
||||
func EvalAny(ell *Ell, body *V, arg *V) (result []V, ok bool) {
|
||||
if body.Type == VTypeString {
|
||||
return []V{*body}, true
|
||||
}
|
||||
var args []V
|
||||
if arg != nil {
|
||||
args = append(args, *arg.Clone())
|
||||
}
|
||||
if res, ok := ell.EvalBlock(body.List, args); ok {
|
||||
return res, true
|
||||
}
|
||||
return nil, false
|
||||
}
|
||||
|
||||
// NewNumber creates a new string value containing a number.
|
||||
func NewNumber(n float64) *V {
|
||||
s := fmt.Sprintf("%f", n)
|
||||
i := len(s)
|
||||
for i > 0 && s[i-1] == '0' {
|
||||
i--
|
||||
}
|
||||
if s[i-1] == '.' {
|
||||
i--
|
||||
}
|
||||
return NewString(s[:i])
|
||||
}
|
||||
|
||||
// Truthy decides whether any value is logically true.
|
||||
func Truthy(v *V) bool {
|
||||
return v != nil && (len(v.List) > 0 || len(v.String) > 0)
|
||||
}
|
||||
|
||||
// NewBoolean creates a new string value copying the boolean's truthiness.
|
||||
func NewBoolean(b bool) *V {
|
||||
if b {
|
||||
return NewString("1")
|
||||
}
|
||||
return NewString("")
|
||||
}
|
||||
|
||||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
|
||||
func fnLocal(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) == 0 || args[0].Type != VTypeList {
|
||||
return ell.Errorf("first argument must be a list")
|
||||
}
|
||||
|
||||
// Duplicates or non-strings don't really matter to us, user's problem.
|
||||
scope := ell.scopes[len(ell.scopes)-1]
|
||||
|
||||
values := args[1:]
|
||||
for _, name := range args[0].List {
|
||||
if len(values) > 0 {
|
||||
scope[name.String] = *values[0].Clone()
|
||||
values = values[1:]
|
||||
}
|
||||
}
|
||||
return nil, true
|
||||
}
|
||||
|
||||
func fnSet(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) == 0 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
|
||||
if len(args) > 1 {
|
||||
result = []V{*args[1].Clone()}
|
||||
ell.Set(args[0].String, &result[0])
|
||||
return result, true
|
||||
}
|
||||
|
||||
// We return an empty list for a nil value.
|
||||
if v := ell.Get(args[0].String); v != nil {
|
||||
result = []V{*v.Clone()}
|
||||
} else {
|
||||
result = []V{*NewList(nil)}
|
||||
}
|
||||
return result, true
|
||||
}
|
||||
|
||||
func fnList(ell *Ell, args []V) (result []V, ok bool) {
|
||||
return []V{*NewList(args)}, true
|
||||
}
|
||||
|
||||
func fnValues(ell *Ell, args []V) (result []V, ok bool) {
|
||||
return args, true
|
||||
}
|
||||
|
||||
func fnIf(ell *Ell, args []V) (result []V, ok bool) {
|
||||
var cond, body, keyword int
|
||||
for cond = 0; ; cond = keyword + 1 {
|
||||
if cond >= len(args) {
|
||||
return ell.Errorf("missing condition")
|
||||
}
|
||||
if body = cond + 1; body >= len(args) {
|
||||
return ell.Errorf("missing body")
|
||||
}
|
||||
|
||||
var res []V
|
||||
if res, ok = EvalAny(ell, &args[cond], nil); !ok {
|
||||
return nil, false
|
||||
}
|
||||
if len(res) > 0 && Truthy(&res[0]) {
|
||||
return EvalAny(ell, &args[body], nil)
|
||||
}
|
||||
|
||||
if keyword = body + 1; keyword >= len(args) {
|
||||
break
|
||||
}
|
||||
if args[keyword].Type != VTypeString {
|
||||
return ell.Errorf("expected keyword, got list")
|
||||
}
|
||||
|
||||
switch kw := args[keyword].String; kw {
|
||||
case "else":
|
||||
if body = keyword + 1; body >= len(args) {
|
||||
return ell.Errorf("missing body")
|
||||
}
|
||||
return EvalAny(ell, &args[body], nil)
|
||||
case "elif":
|
||||
default:
|
||||
return ell.Errorf("invalid keyword: %s", kw)
|
||||
}
|
||||
}
|
||||
return nil, true
|
||||
}
|
||||
|
||||
func fnMap(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 {
|
||||
return ell.Errorf("first argument must be a function")
|
||||
}
|
||||
if len(args) < 2 || args[0].Type != VTypeList {
|
||||
return ell.Errorf("second argument must be a list")
|
||||
}
|
||||
|
||||
body, values := &args[0], &args[1]
|
||||
for _, v := range values.List {
|
||||
res, ok := EvalAny(ell, body, &v)
|
||||
if !ok {
|
||||
return nil, false
|
||||
}
|
||||
result = append(result, res...)
|
||||
}
|
||||
return []V{*NewList(result)}, true
|
||||
}
|
||||
|
||||
func fnPrint(ell *Ell, args []V) (result []V, ok bool) {
|
||||
for _, arg := range args {
|
||||
if arg.Type != VTypeString {
|
||||
PrintV(os.Stdout, &arg)
|
||||
} else if _, err := os.Stdout.WriteString(arg.String); err != nil {
|
||||
return ell.Errorf("write failed: %s", err)
|
||||
}
|
||||
}
|
||||
return nil, true
|
||||
}
|
||||
|
||||
func fnCat(ell *Ell, args []V) (result []V, ok bool) {
|
||||
buf := bytes.NewBuffer(nil)
|
||||
for _, arg := range args {
|
||||
if arg.Type != VTypeString {
|
||||
PrintV(buf, &arg)
|
||||
} else {
|
||||
buf.WriteString(arg.String)
|
||||
}
|
||||
}
|
||||
return []V{*NewString(buf.String())}, true
|
||||
}
|
||||
|
||||
func fnSystem(ell *Ell, args []V) (result []V, ok bool) {
|
||||
var argv []string
|
||||
for _, arg := range args {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
argv = append(argv, arg.String)
|
||||
}
|
||||
if len(argv) == 0 {
|
||||
return ell.Errorf("command name required")
|
||||
}
|
||||
|
||||
cmd := exec.Command(argv[0], argv[1:]...)
|
||||
cmd.Stdin = os.Stdin
|
||||
cmd.Stdout = os.Stdout
|
||||
cmd.Stderr = os.Stderr
|
||||
|
||||
// Approximation of system(3) return value to match C ell at least a bit.
|
||||
if err := cmd.Run(); err == nil {
|
||||
return []V{*NewNumber(0)}, true
|
||||
} else if _, ok := err.(*exec.Error); ok {
|
||||
return ell.Errorf("%s", err)
|
||||
} else {
|
||||
return []V{*NewNumber(1)}, true
|
||||
}
|
||||
}
|
||||
|
||||
func fnParse(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
|
||||
res, err := NewParser([]byte(args[0].String)).Run()
|
||||
if err != nil {
|
||||
return ell.Errorf("%s", err)
|
||||
}
|
||||
return []V{*NewList(res)}, true
|
||||
}
|
||||
|
||||
func fnTry(ell *Ell, args []V) (result []V, ok bool) {
|
||||
var body, handler *V
|
||||
if len(args) < 1 {
|
||||
return ell.Errorf("first argument must be a function")
|
||||
}
|
||||
if len(args) < 2 {
|
||||
return ell.Errorf("second argument must be a function")
|
||||
}
|
||||
body, handler = &args[0], &args[1]
|
||||
if result, ok = EvalAny(ell, body, nil); ok {
|
||||
return
|
||||
}
|
||||
|
||||
msg := NewString(ell.Error)
|
||||
ell.Error = ""
|
||||
return EvalAny(ell, handler, msg)
|
||||
}
|
||||
|
||||
func fnThrow(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
return ell.Errorf("%s", args[0].String)
|
||||
}
|
||||
|
||||
func fnPlus(ell *Ell, args []V) (result []V, ok bool) {
|
||||
res := 0.
|
||||
for _, arg := range args {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
var value float64
|
||||
if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
|
||||
return ell.Errorf("invalid number: %s", arg.String)
|
||||
}
|
||||
res += value
|
||||
}
|
||||
return []V{*NewNumber(res)}, true
|
||||
}
|
||||
|
||||
func fnMinus(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
|
||||
var res float64
|
||||
if n, _ := fmt.Sscan(args[0].String, &res); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", args[0].String)
|
||||
}
|
||||
if len(args) == 1 {
|
||||
res = -res
|
||||
}
|
||||
|
||||
for _, arg := range args[1:] {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
var value float64
|
||||
if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", arg.String)
|
||||
}
|
||||
res -= value
|
||||
}
|
||||
return []V{*NewNumber(res)}, true
|
||||
}
|
||||
|
||||
func fnMultiply(ell *Ell, args []V) (result []V, ok bool) {
|
||||
res := 1.
|
||||
for _, arg := range args {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
var value float64
|
||||
if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
|
||||
return ell.Errorf("invalid number: %s", arg.String)
|
||||
}
|
||||
res *= value
|
||||
}
|
||||
return []V{*NewNumber(res)}, true
|
||||
}
|
||||
|
||||
func fnDivide(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
|
||||
var res float64
|
||||
if n, _ := fmt.Sscan(args[0].String, &res); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", args[0].String)
|
||||
}
|
||||
for _, arg := range args[1:] {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
var value float64
|
||||
if n, _ := fmt.Sscan(arg.String, &value); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", arg.String)
|
||||
}
|
||||
res /= value
|
||||
}
|
||||
return []V{*NewNumber(res)}, true
|
||||
}
|
||||
|
||||
func fnNot(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 {
|
||||
return ell.Errorf("missing argument")
|
||||
}
|
||||
return []V{*NewBoolean(!Truthy(&args[0]))}, true
|
||||
}
|
||||
|
||||
func fnAnd(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if args == nil {
|
||||
return []V{*NewBoolean(true)}, true
|
||||
}
|
||||
for _, arg := range args {
|
||||
result, ok = EvalAny(ell, &arg, nil)
|
||||
if !ok {
|
||||
return nil, false
|
||||
}
|
||||
if len(result) < 1 || !Truthy(&result[0]) {
|
||||
return []V{*NewBoolean(false)}, true
|
||||
}
|
||||
}
|
||||
return result, true
|
||||
}
|
||||
|
||||
func fnOr(ell *Ell, args []V) (result []V, ok bool) {
|
||||
for _, arg := range args {
|
||||
result, ok = EvalAny(ell, &arg, nil)
|
||||
if !ok {
|
||||
return nil, false
|
||||
}
|
||||
if len(result) > 0 && Truthy(&result[0]) {
|
||||
return result, true
|
||||
}
|
||||
}
|
||||
return []V{*NewBoolean(false)}, true
|
||||
}
|
||||
|
||||
func fnEq(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
etalon, res := args[0].String, true
|
||||
for _, arg := range args[1:] {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
if res = etalon == arg.String; !res {
|
||||
break
|
||||
}
|
||||
}
|
||||
return []V{*NewBoolean(res)}, true
|
||||
}
|
||||
|
||||
func fnLt(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
etalon, res := args[0].String, true
|
||||
for _, arg := range args[1:] {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
if res = etalon < arg.String; !res {
|
||||
break
|
||||
}
|
||||
etalon = arg.String
|
||||
}
|
||||
return []V{*NewBoolean(res)}, true
|
||||
}
|
||||
|
||||
func fnEquals(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
var first, second float64
|
||||
if n, _ := fmt.Sscan(args[0].String, &first); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", args[0].String)
|
||||
}
|
||||
res := true
|
||||
for _, arg := range args[1:] {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
if n, _ := fmt.Sscan(arg.String, &second); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", arg.String)
|
||||
}
|
||||
if res = first == second; !res {
|
||||
break
|
||||
}
|
||||
first = second
|
||||
}
|
||||
return []V{*NewBoolean(res)}, true
|
||||
}
|
||||
|
||||
func fnLess(ell *Ell, args []V) (result []V, ok bool) {
|
||||
if len(args) < 1 || args[0].Type != VTypeString {
|
||||
return ell.Errorf("first argument must be string")
|
||||
}
|
||||
var first, second float64
|
||||
if n, _ := fmt.Sscan(args[0].String, &first); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", args[0].String)
|
||||
}
|
||||
res := true
|
||||
for _, arg := range args[1:] {
|
||||
if arg.Type != VTypeString {
|
||||
return ell.Errorf("arguments must be strings")
|
||||
}
|
||||
if n, _ := fmt.Sscan(arg.String, &second); n < 1 {
|
||||
return ell.Errorf("invalid number: %f", arg.String)
|
||||
}
|
||||
if res = first < second; !res {
|
||||
break
|
||||
}
|
||||
first = second
|
||||
}
|
||||
return []V{*NewBoolean(res)}, true
|
||||
}
|
||||
|
||||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
|
||||
var stdNative = map[string]Handler{
|
||||
"local": fnLocal,
|
||||
"set": fnSet,
|
||||
"list": fnList,
|
||||
"values": fnValues,
|
||||
"if": fnIf,
|
||||
"map": fnMap,
|
||||
"print": fnPrint,
|
||||
"..": fnCat,
|
||||
"system": fnSystem,
|
||||
"parse": fnParse,
|
||||
"try": fnTry,
|
||||
"throw": fnThrow,
|
||||
"+": fnPlus,
|
||||
"-": fnMinus,
|
||||
"*": fnMultiply,
|
||||
"/": fnDivide,
|
||||
"not": fnNot,
|
||||
"and": fnAnd,
|
||||
"or": fnOr,
|
||||
"eq?": fnEq,
|
||||
"lt?": fnLt,
|
||||
"=": fnEquals,
|
||||
"<": fnLess,
|
||||
}
|
||||
|
||||
var stdComposed = `
|
||||
set unless { if (not (@1)) @2 }
|
||||
set filter { local [_body _list] @1 @2;
|
||||
map { if (@_body @1) { @1 } } @_list }
|
||||
set for { local [_list _body] @1 @2;
|
||||
try { map { @_body @1 } @_list } { if (ne? @1 _break) { throw @1 } } }
|
||||
|
||||
set break { throw _break }
|
||||
|
||||
# TODO: we should be able to apply them to all arguments
|
||||
set ne? { not (eq? @1 @2) }; set le? { ge? @2 @1 }
|
||||
set ge? { not (lt? @1 @2) }; set gt? { lt? @2 @1 }
|
||||
set <> { not (= @1 @2) }; set <= { >= @2 @1 }
|
||||
set >= { not (< @1 @2) }; set > { < @2 @1 }`
|
||||
|
||||
// StdInitialize initializes the ell standard library.
|
||||
func StdInitialize(ell *Ell) bool {
|
||||
for name, handler := range stdNative {
|
||||
ell.Native[name] = handler
|
||||
}
|
||||
|
||||
p := NewParser([]byte(stdComposed))
|
||||
program, err := p.Run()
|
||||
if err != nil {
|
||||
return false
|
||||
}
|
||||
|
||||
_, ok := ell.EvalBlock(program, nil)
|
||||
return ok
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user