Initial commit: Go 1.23 release state

test/ken/rob2.go

@@ -0,0 +1,280 @@
+// run
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test general operation using s-list.
+// First Go program ever run (although not in this exact form).
+
+package main
+
+import "fmt"
+
+const nilchar = 0
+
+type Atom struct {
+	str     string
+	integer int
+	next    *Slist /* in hash bucket */
+}
+
+type List struct {
+	car *Slist
+	cdr *Slist
+}
+
+type Slist struct {
+	isatom   bool
+	isstring bool
+	//union {
+	atom Atom
+	list List
+	//} u;
+
+}
+
+func (this *Slist) Car() *Slist {
+	return this.list.car
+}
+
+func (this *Slist) Cdr() *Slist {
+	return this.list.cdr
+}
+
+func (this *Slist) String() string {
+	return this.atom.str
+}
+
+func (this *Slist) Integer() int {
+	return this.atom.integer
+}
+
+func (slist *Slist) Free() {
+	if slist == nil {
+		return
+	}
+	if slist.isatom {
+		//		free(slist.String());
+	} else {
+		slist.Car().Free()
+		slist.Cdr().Free()
+	}
+	//	free(slist);
+}
+
+//Slist* atom(byte *s, int i);
+
+var token int
+var peekc int = -1
+var lineno int32 = 1
+
+var input string
+var inputindex int = 0
+var tokenbuf [100]byte
+var tokenlen int = 0
+
+const EOF int = -1
+
+func main() {
+	var list *Slist
+
+	OpenFile()
+	for {
+		list = Parse()
+		if list == nil {
+			break
+		}
+		r := list.Print()
+		list.Free()
+		if r != "(defn foo (add 12 34))" {
+			panic(r)
+		}
+		break
+	}
+}
+
+func (slist *Slist) PrintOne(doparen bool) string {
+	if slist == nil {
+		return ""
+	}
+	var r string
+	if slist.isatom {
+		if slist.isstring {
+			r = slist.String()
+		} else {
+			r = fmt.Sprintf("%v", slist.Integer())
+		}
+	} else {
+		if doparen {
+			r += "("
+		}
+		r += slist.Car().PrintOne(true)
+		if slist.Cdr() != nil {
+			r += " "
+			r += slist.Cdr().PrintOne(false)
+		}
+		if doparen {
+			r += ")"
+		}
+	}
+	return r
+}
+
+func (slist *Slist) Print() string {
+	return slist.PrintOne(true)
+}
+
+func Get() int {
+	var c int
+
+	if peekc >= 0 {
+		c = peekc
+		peekc = -1
+	} else {
+		c = int(input[inputindex])
+		inputindex++
+		if c == '\n' {
+			lineno = lineno + 1
+		}
+		if c == nilchar {
+			inputindex = inputindex - 1
+			c = EOF
+		}
+	}
+	return c
+}
+
+func WhiteSpace(c int) bool {
+	return c == ' ' || c == '\t' || c == '\r' || c == '\n'
+}
+
+func NextToken() {
+	var i, c int
+
+	tokenbuf[0] = nilchar // clear previous token
+	c = Get()
+	for WhiteSpace(c) {
+		c = Get()
+	}
+	switch c {
+	case EOF:
+		token = EOF
+	case '(', ')':
+		token = c
+		break
+	default:
+		for i = 0; i < 100-1; { // sizeof tokenbuf - 1
+			tokenbuf[i] = byte(c)
+			i = i + 1
+			c = Get()
+			if c == EOF {
+				break
+			}
+			if WhiteSpace(c) || c == ')' {
+				peekc = c
+				break
+			}
+		}
+		if i >= 100-1 { // sizeof tokenbuf - 1
+			panic("atom too long\n")
+		}
+		tokenlen = i
+		tokenbuf[i] = nilchar
+		if '0' <= tokenbuf[0] && tokenbuf[0] <= '9' {
+			token = '0'
+		} else {
+			token = 'A'
+		}
+	}
+}
+
+func Expect(c int) {
+	if token != c {
+		print("parse error: expected ", c, "\n")
+		panic("parse")
+	}
+	NextToken()
+}
+
+// Parse a non-parenthesized list up to a closing paren or EOF
+func ParseList() *Slist {
+	var slist, retval *Slist
+
+	slist = new(Slist)
+	slist.list.car = nil
+	slist.list.cdr = nil
+	slist.isatom = false
+	slist.isstring = false
+
+	retval = slist
+	for {
+		slist.list.car = Parse()
+		if token == ')' || token == EOF { // empty cdr
+			break
+		}
+		slist.list.cdr = new(Slist)
+		slist = slist.list.cdr
+	}
+	return retval
+}
+
+func atom(i int) *Slist { // BUG: uses tokenbuf; should take argument)
+	var slist *Slist
+
+	slist = new(Slist)
+	if token == '0' {
+		slist.atom.integer = i
+		slist.isstring = false
+	} else {
+		slist.atom.str = string(tokenbuf[0:tokenlen])
+		slist.isstring = true
+	}
+	slist.isatom = true
+	return slist
+}
+
+func atoi() int { // BUG: uses tokenbuf; should take argument)
+	var v int = 0
+	for i := 0; i < tokenlen && '0' <= tokenbuf[i] && tokenbuf[i] <= '9'; i = i + 1 {
+		v = 10*v + int(tokenbuf[i]-'0')
+	}
+	return v
+}
+
+func Parse() *Slist {
+	var slist *Slist
+
+	if token == EOF || token == ')' {
+		return nil
+	}
+	if token == '(' {
+		NextToken()
+		slist = ParseList()
+		Expect(')')
+		return slist
+	} else {
+		// Atom
+		switch token {
+		case EOF:
+			return nil
+		case '0':
+			slist = atom(atoi())
+		case '"', 'A':
+			slist = atom(0)
+		default:
+			slist = nil
+			print("unknown token: ", token, "\n")
+		}
+		NextToken()
+		return slist
+	}
+	return nil
+}
+
+func OpenFile() {
+	input = "(defn foo (add 12 34))\n\x00"
+	inputindex = 0
+	peekc = -1 // BUG
+	NextToken()
+}