From f4f03d1737b651f9a70453ab9f2cdee11c0c8225 Mon Sep 17 00:00:00 2001 From: Přemysl Janouch Date: Wed, 10 Oct 2018 16:37:25 +0200 Subject: Go: use slices for Handler arguments First step to replacing linked lists with something more Go-like. --- ell/ell.go | 290 ++++++++++++++++++++++++++++++++----------------------------- 1 file changed, 150 insertions(+), 140 deletions(-) diff --git a/ell/ell.go b/ell/ell.go index 84d1bc3..f07617e 100644 --- a/ell/ell.go +++ b/ell/ell.go @@ -545,7 +545,7 @@ func (p *Parser) Run() (result *V, err error) { // --- Runtime ----------------------------------------------------------------- // Handler is a Go handler for an Ell function. -type Handler func(*Ell, *V, **V) bool +type Handler func(*Ell, []V, **V) bool // Ell is an interpreter context. type Ell struct { @@ -666,7 +666,15 @@ func (ell *Ell) evalNative(name string, args *V, result **V) bool { if !ell.evalArgs(args, &arguments) { return false } - return fn(ell, arguments, result) + // FIXME: Must change V.Head to a slice, too! This is just a provisional + // change to not have to do both at once! Lots of copying this way. + var sliced []V + for ; arguments != nil; arguments = arguments.Next { + singledOut := *arguments + singledOut.Next = nil + sliced = append(sliced, singledOut) + } + return fn(ell, sliced, result) } func (ell *Ell) evalResolved(body *V, args *V, result **V) bool { @@ -807,40 +815,37 @@ func NewBoolean(b bool) *V { // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -func fnLocal(ell *Ell, args *V, result **V) bool { - names := args - if names == nil || names.Type != VTypeList { +func fnLocal(ell *Ell, args []V, result **V) 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.Head - values := names.Next - for names = names.Head; names != nil; names = names.Next { - scopePrepend(scope, string(names.String), values.Clone()) - if values != nil { - values = values.Next + values := args[1:] + for name := args[0].Head; name != nil; name = name.Next { + scopePrepend(scope, string(name.String), values[0].Clone()) + if len(values) > 0 { + values = values[1:] } } return true } -func fnSet(ell *Ell, args *V, result **V) bool { - name := args - if name == nil || name.Type != VTypeString { +func fnSet(ell *Ell, args []V, result **V) bool { + if len(args) == 0 || args[0].Type != VTypeString { return ell.Errorf("first argument must be string") } - v := name.Next - if v != nil { - *result = v.Clone() - ell.Set(string(name.String), v) + if len(args) > 1 { + *result = args[1].Clone() + ell.Set(args[0].String, *result) return true } // We return an empty list for a nil value. - if v = ell.Get(string(name.String)); v != nil { + if v := ell.Get(args[0].String); v != nil { *result = v.Clone() } else { *result = NewList(nil) @@ -848,47 +853,56 @@ func fnSet(ell *Ell, args *V, result **V) bool { return true } -func fnList(ell *Ell, args *V, result **V) bool { - *result = NewList(args.CloneSeq()) +func sliceToSeq(slice []V) (res *V) { + out := &res + for _, v := range slice { + *out = v.Clone() + out = &(*out).Next + } + return +} + +func fnList(ell *Ell, args []V, result **V) bool { + *result = NewList(sliceToSeq(args)) return true } -func fnValues(ell *Ell, args *V, result **V) bool { - *result = args.CloneSeq() +func fnValues(ell *Ell, args []V, result **V) bool { + *result = sliceToSeq(args) return true } -func fnIf(ell *Ell, args *V, result **V) bool { - var cond, body, keyword *V - for cond = args; ; cond = keyword.Next { - if cond == nil { +func fnIf(ell *Ell, args []V, result **V) bool { + var cond, body, keyword int + for cond = 0; ; cond = keyword + 1 { + if cond >= len(args) { return ell.Errorf("missing condition") } - if body = cond.Next; body == nil { + if body = cond + 1; body >= len(args) { return ell.Errorf("missing body") } var res *V - if !EvalAny(ell, cond, nil, &res) { + if !EvalAny(ell, &args[cond], nil, &res) { return false } if Truthy(res) { - return EvalAny(ell, body, nil, result) + return EvalAny(ell, &args[body], nil, result) } - if keyword = body.Next; keyword == nil { + if keyword = body + 1; keyword >= len(args) { break } - if keyword.Type != VTypeString { + if args[keyword].Type != VTypeString { return ell.Errorf("expected keyword, got list") } - switch kw := string(keyword.String); kw { + switch kw := args[keyword].String; kw { case "else": - if body = keyword.Next; body == nil { + if body = keyword + 1; body >= len(args) { return ell.Errorf("missing body") } - return EvalAny(ell, body, nil, result) + return EvalAny(ell, &args[body], nil, result) case "elif": default: return ell.Errorf("invalid keyword: %s", kw) @@ -897,15 +911,16 @@ func fnIf(ell *Ell, args *V, result **V) bool { return true } -func fnMap(ell *Ell, args *V, result **V) bool { - var body, values *V - if body = args; body == nil { +func fnMap(ell *Ell, args []V, result **V) bool { + if len(args) < 1 { return ell.Errorf("first argument must be a function") } - if values = body.Next; values == nil || values.Type != VTypeList { + if len(args) < 2 || args[0].Type != VTypeList { return ell.Errorf("second argument must be a list") } + body, values := &args[0], &args[1] + var res *V out := &res @@ -921,37 +936,37 @@ func fnMap(ell *Ell, args *V, result **V) bool { return true } -func fnPrint(ell *Ell, args *V, result **V) bool { - for ; args != nil; args = args.Next { - if args.Type != VTypeString { - PrintV(os.Stdout, args) - } else if _, err := os.Stdout.WriteString(args.String); err != nil { +func fnPrint(ell *Ell, args []V, result **V) 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 true } -func fnCat(ell *Ell, args *V, result **V) bool { +func fnCat(ell *Ell, args []V, result **V) bool { buf := bytes.NewBuffer(nil) - for ; args != nil; args = args.Next { - if args.Type != VTypeString { - PrintV(buf, args) + for _, arg := range args { + if arg.Type != VTypeString { + PrintV(buf, &arg) } else { - buf.WriteString(args.String) + buf.WriteString(arg.String) } } *result = NewString(buf.String()) return true } -func fnSystem(ell *Ell, args *V, result **V) bool { +func fnSystem(ell *Ell, args []V, result **V) bool { var argv []string - for ; args != nil; args = args.Next { - if args.Type != VTypeString { + for _, arg := range args { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - argv = append(argv, string(args.String)) + argv = append(argv, string(arg.String)) } if len(argv) == 0 { return ell.Errorf("command name required") @@ -973,13 +988,12 @@ func fnSystem(ell *Ell, args *V, result **V) bool { return true } -func fnParse(ell *Ell, args *V, result **V) bool { - body := args - if body == nil || body.Type != VTypeString { +func fnParse(ell *Ell, args []V, result **V) bool { + if len(args) < 1 || args[0].Type != VTypeString { return ell.Errorf("first argument must be string") } - res, err := NewParser([]byte(body.String)).Run() + res, err := NewParser([]byte(args[0].String)).Run() if err != nil { return ell.Errorf("%s", err) } @@ -987,14 +1001,15 @@ func fnParse(ell *Ell, args *V, result **V) bool { return true } -func fnTry(ell *Ell, args *V, result **V) bool { +func fnTry(ell *Ell, args []V, result **V) bool { var body, handler *V - if body = args; body == nil { + if len(args) < 1 { return ell.Errorf("first argument must be a function") } - if handler = body.Next; handler == nil { + if len(args) < 2 { return ell.Errorf("second argument must be a function") } + body, handler = &args[0], &args[1] if EvalAny(ell, body, nil, result) { return true } @@ -1006,112 +1021,111 @@ func fnTry(ell *Ell, args *V, result **V) bool { return EvalAny(ell, handler, msg, result) } -func fnThrow(ell *Ell, args *V, result **V) bool { - message := args - if message == nil || message.Type != VTypeString { +func fnThrow(ell *Ell, args []V, result **V) bool { + if len(args) < 1 || args[0].Type != VTypeString { return ell.Errorf("first argument must be string") } - return ell.Errorf("%s", message.String) + return ell.Errorf("%s", args[0].String) } -func fnPlus(ell *Ell, args *V, result **V) bool { +func fnPlus(ell *Ell, args []V, result **V) bool { res := 0. - for ; args != nil; args = args.Next { - if args.Type != VTypeString { + for _, arg := range args { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - var arg float64 - if n, _ := fmt.Sscan(string(args.String), &arg); n < 1 { - return ell.Errorf("invalid number: %s", args.String) + var value float64 + if n, _ := fmt.Sscan(arg.String, &value); n < 1 { + return ell.Errorf("invalid number: %s", arg.String) } - res += arg + res += value } *result = NewNumber(res) return true } -func fnMinus(ell *Ell, args *V, result **V) bool { - if args == nil || args.Type != VTypeString { +func fnMinus(ell *Ell, args []V, result **V) bool { + if len(args) < 1 || args[0].Type != VTypeString { return ell.Errorf("first argument must be string") } var res float64 - if n, _ := fmt.Sscan(string(args.String), &res); n < 1 { - return ell.Errorf("invalid number: %f", args.String) + if n, _ := fmt.Sscan(args[0].String, &res); n < 1 { + return ell.Errorf("invalid number: %f", args[0].String) } - if args = args.Next; args == nil { + if len(args) == 1 { res = -res } - for ; args != nil; args = args.Next { - if args.Type != VTypeString { + for _, arg := range args[1:] { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - var arg float64 - if n, _ := fmt.Sscan(string(args.String), &arg); n < 1 { - return ell.Errorf("invalid number: %f", args.String) + var value float64 + if n, _ := fmt.Sscan(arg.String, &value); n < 1 { + return ell.Errorf("invalid number: %f", arg.String) } - res -= arg + res -= value } *result = NewNumber(res) return true } -func fnMultiply(ell *Ell, args *V, result **V) bool { +func fnMultiply(ell *Ell, args []V, result **V) bool { res := 1. - for ; args != nil; args = args.Next { - if args.Type != VTypeString { + for _, arg := range args { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - var arg float64 - if n, _ := fmt.Sscan(string(args.String), &arg); n < 1 { - return ell.Errorf("invalid number: %s", args.String) + var value float64 + if n, _ := fmt.Sscan(arg.String, &value); n < 1 { + return ell.Errorf("invalid number: %s", arg.String) } - res *= arg + res *= value } *result = NewNumber(res) return true } -func fnDivide(ell *Ell, args *V, result **V) bool { - if args == nil || args.Type != VTypeString { +func fnDivide(ell *Ell, args []V, result **V) bool { + if len(args) < 1 || args[0].Type != VTypeString { return ell.Errorf("first argument must be string") } var res float64 - if n, _ := fmt.Sscan(string(args.String), &res); n < 1 { - return ell.Errorf("invalid number: %f", args.String) + if n, _ := fmt.Sscan(args[0].String, &res); n < 1 { + return ell.Errorf("invalid number: %f", args[0].String) } - for args = args.Next; args != nil; args = args.Next { - if args.Type != VTypeString { + for _, arg := range args[1:] { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - var arg float64 - if n, _ := fmt.Sscan(string(args.String), &arg); n < 1 { - return ell.Errorf("invalid number: %f", args.String) + var value float64 + if n, _ := fmt.Sscan(arg.String, &value); n < 1 { + return ell.Errorf("invalid number: %f", arg.String) } - res /= arg + res /= value } *result = NewNumber(res) return true } -func fnNot(ell *Ell, args *V, result **V) bool { - if args == nil { +func fnNot(ell *Ell, args []V, result **V) bool { + if len(args) < 1 { return ell.Errorf("missing argument") } - *result = NewBoolean(!Truthy(args)) + *result = NewBoolean(!Truthy(&args[0])) return true } -func fnAnd(ell *Ell, args *V, result **V) bool { +func fnAnd(ell *Ell, args []V, result **V) bool { if args == nil { *result = NewBoolean(true) return true } - for ; args != nil; args = args.Next { + for _, arg := range args { *result = nil - if !EvalAny(ell, args, nil, result) { + if !EvalAny(ell, &arg, nil, result) { return false } if !Truthy(*result) { @@ -1122,9 +1136,9 @@ func fnAnd(ell *Ell, args *V, result **V) bool { return true } -func fnOr(ell *Ell, args *V, result **V) bool { - for ; args != nil; args = args.Next { - if !EvalAny(ell, args, nil, result) { +func fnOr(ell *Ell, args []V, result **V) bool { + for _, arg := range args { + if !EvalAny(ell, &arg, nil, result) { return false } if Truthy(*result) { @@ -1136,17 +1150,16 @@ func fnOr(ell *Ell, args *V, result **V) bool { return true } -func fnEq(ell *Ell, args *V, result **V) bool { - etalon := args - if etalon == nil || etalon.Type != VTypeString { +func fnEq(ell *Ell, args []V, result **V) bool { + if len(args) < 1 || args[0].Type != VTypeString { return ell.Errorf("first argument must be string") } - res := true - for args = etalon.Next; args != nil; args = args.Next { - if args.Type != VTypeString { + etalon, res := args[0].String, true + for _, arg := range args[1:] { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - if res = string(etalon.String) == string(args.String); !res { + if res = etalon == arg.String; !res { break } } @@ -1154,41 +1167,39 @@ func fnEq(ell *Ell, args *V, result **V) bool { return true } -func fnLt(ell *Ell, args *V, result **V) bool { - etalon := args - if etalon == nil || etalon.Type != VTypeString { +func fnLt(ell *Ell, args []V, result **V) bool { + if len(args) < 1 || args[0].Type != VTypeString { return ell.Errorf("first argument must be string") } - res := true - for args = etalon.Next; args != nil; args = args.Next { - if args.Type != VTypeString { + etalon, res := args[0].String, true + for _, arg := range args[1:] { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - if res = string(etalon.String) < string(args.String); !res { + if res = etalon < arg.String; !res { break } - etalon = args + etalon = arg.String } *result = NewBoolean(res) return true } -func fnEquals(ell *Ell, args *V, result **V) bool { - etalon := args - if etalon == nil || etalon.Type != VTypeString { +func fnEquals(ell *Ell, args []V, result **V) 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(string(etalon.String), &first); n < 1 { - return ell.Errorf("invalid number: %f", etalon.String) + if n, _ := fmt.Sscan(args[0].String, &first); n < 1 { + return ell.Errorf("invalid number: %f", args[0].String) } res := true - for args = etalon.Next; args != nil; args = args.Next { - if args.Type != VTypeString { + for _, arg := range args[1:] { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - if n, _ := fmt.Sscan(string(args.String), &second); n < 1 { - return ell.Errorf("invalid number: %f", args.String) + if n, _ := fmt.Sscan(arg.String, &second); n < 1 { + return ell.Errorf("invalid number: %f", arg.String) } if res = first == second; !res { break @@ -1199,22 +1210,21 @@ func fnEquals(ell *Ell, args *V, result **V) bool { return true } -func fnLess(ell *Ell, args *V, result **V) bool { - etalon := args - if etalon == nil || etalon.Type != VTypeString { +func fnLess(ell *Ell, args []V, result **V) 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(string(etalon.String), &first); n < 1 { - return ell.Errorf("invalid number: %f", etalon.String) + if n, _ := fmt.Sscan(args[0].String, &first); n < 1 { + return ell.Errorf("invalid number: %f", args[0].String) } res := true - for args = etalon.Next; args != nil; args = args.Next { - if args.Type != VTypeString { + for _, arg := range args[1:] { + if arg.Type != VTypeString { return ell.Errorf("arguments must be strings") } - if n, _ := fmt.Sscan(string(args.String), &second); n < 1 { - return ell.Errorf("invalid number: %f", args.String) + if n, _ := fmt.Sscan(arg.String, &second); n < 1 { + return ell.Errorf("invalid number: %f", arg.String) } if res = first < second; !res { break -- cgit v1.2.3-70-g09d2