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// +build OMIT
package main
// fake stuff
type char uint8;
// const char TESTSTRING[] = "(defn foo (add 'a 'b))\n";
type Atom struct {
string *[100]char;
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;
Free method();
Print method();
PrintOne method(doparen bool);
String method(*char <-);
Integer method(int <-);
Car method(*Slist <-);
Cdr method(*Slist <-);
}
method (this *Slist) Car(*Slist <-) {
return this.list.car;
}
method (this *Slist) Cdr(*Slist <-) {
return this.list.cdr;
}
method (this *Slist) String(*[100]char <-) {
return this.atom.string;
}
method (this *Slist) Integer(int <-) {
return this.atom.integer;
}
function OpenFile();
function Parse(*Slist <-);
//Slist* atom(char *s, int i);
var token int;
var peekc int = -1;
var lineno int32 = 1;
var input [100*1000]char;
var inputindex int = 0;
var tokenbuf [100]char;
var EOF int = -1; // BUG should be const
function main(int32 <-) {
var list *Slist;
OpenFile();
for ;; {
list = Parse();
if list == nil {
break;
}
list.Print();
list.Free();
break;
}
return 0;
}
method (slist *Slist) Free(<-) {
if slist == nil {
return;
}
if slist.isatom {
// free(slist.String());
} else {
slist.Car().Free();
slist.Cdr().Free();
}
// free(slist);
}
method (slist *Slist) PrintOne(<- doparen bool) {
if slist == nil {
return;
}
if slist.isatom {
if slist.isstring {
print(slist.String());
} else {
print(slist.Integer());
}
} else {
if doparen {
print("(");
}
slist.Car().PrintOne(true);
if slist.Cdr() != nil {
print(" ");
slist.Cdr().PrintOne(false);
}
if doparen {
print(")");
}
}
}
method (slist *Slist) Print() {
slist.PrintOne(true);
print "\n";
}
function Get(int <-) {
var c int;
if peekc >= 0 {
c = peekc;
peekc = -1;
} else {
c = convert(int, input[inputindex]);
inputindex = inputindex + 1; // BUG should be incr one expr
if c == '\n' {
lineno = lineno + 1;
}
if c == '\0' {
inputindex = inputindex - 1;
c = EOF;
}
}
return c;
}
function WhiteSpace(bool <- c int) {
return c == ' ' || c == '\t' || c == '\r' || c == '\n';
}
function NextToken() {
var i, c int;
var backslash bool;
tokenbuf[0] = '\0'; // clear previous token
c = Get();
while WhiteSpace(c) {
c = Get();
}
switch c {
case EOF:
token = EOF;
case '(':
case ')':
token = c;
break;
case:
for i = 0; i < 100 - 1; { // sizeof tokenbuf - 1
tokenbuf[i] = convert(char, 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";
}
tokenbuf[i] = '\0';
if '0' <= tokenbuf[0] && tokenbuf[0] <= '9' {
token = '0';
} else {
token = 'A';
}
}
}
function 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
function 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 == ')' { // empty cdr
break;
}
if token == EOF { // empty cdr BUG SHOULD USE ||
break;
}
slist.list.cdr = new(Slist);
slist = slist.list.cdr;
}
return retval;
}
function atom(*Slist <- i int) { // BUG: uses tokenbuf; should take argument
var h, length int;
var slist, tail *Slist;
slist = new(Slist);
if token == '0' {
slist.atom.integer = i;
slist.isstring = false;
} else {
slist.atom.string = new([100]char);
var i int;
for i = 0; ; i = i + 1 {
(*slist.atom.string)[i] = tokenbuf[i];
if tokenbuf[i] == '\0' {
break;
}
}
//slist.atom.string = "hello"; // BUG! s; //= strdup(s);
slist.isstring = true;
}
slist.isatom = true;
return slist;
}
function atoi(int <-) { // BUG: uses tokenbuf; should take argument
var v int = 0;
for i := 0; '0' <= tokenbuf[i] && tokenbuf[i] <= '9'; i = i + 1 {
v = 10 * v + convert(int, tokenbuf[i] - '0');
}
return v;
}
function 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 '"':
case 'A':
slist = atom(0);
case:
slist = nil;
print "unknown token"; //, token, tokenbuf;
}
NextToken();
return slist;
}
return nil;
}
function OpenFile() {
//strcpy(input, TESTSTRING);
//inputindex = 0;
// (defn foo (add 12 34))\n
inputindex = 0;
peekc = -1; // BUG
EOF = -1; // BUG
i := 0;
input[i] = '('; i = i + 1;
input[i] = 'd'; i = i + 1;
input[i] = 'e'; i = i + 1;
input[i] = 'f'; i = i + 1;
input[i] = 'n'; i = i + 1;
input[i] = ' '; i = i + 1;
input[i] = 'f'; i = i + 1;
input[i] = 'o'; i = i + 1;
input[i] = 'o'; i = i + 1;
input[i] = ' '; i = i + 1;
input[i] = '('; i = i + 1;
input[i] = 'a'; i = i + 1;
input[i] = 'd'; i = i + 1;
input[i] = 'd'; i = i + 1;
input[i] = ' '; i = i + 1;
input[i] = '1'; i = i + 1;
input[i] = '2'; i = i + 1;
input[i] = ' '; i = i + 1;
input[i] = '3'; i = i + 1;
input[i] = '4'; i = i + 1;
input[i] = ')'; i = i + 1;
input[i] = ')'; i = i + 1;
input[i] = '\n'; i = i + 1;
NextToken();
}
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