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-rw-r--r--usr/gri/src/parser.go19
-rw-r--r--usr/gri/src/scanner.go67
-rw-r--r--usr/gri/src/test_parser.go10
-rw-r--r--usr/gri/src/test_scanner.go11
4 files changed, 56 insertions, 51 deletions
diff --git a/usr/gri/src/parser.go b/usr/gri/src/parser.go
index b14c77805..49b0f6ab2 100644
--- a/usr/gri/src/parser.go
+++ b/usr/gri/src/parser.go
@@ -4,7 +4,6 @@
package Parser
-//import . "scanner"
import Scanner "scanner"
@@ -63,8 +62,8 @@ func (P *Parser) Open(S *Scanner.Scanner, verbose int) {
}
-func (P *Parser) Error(msg string) {
- P.S.Error(P.S.pos, msg);
+func (P *Parser) Error(pos int, msg string) {
+ P.S.Error(pos, msg);
P.Next(); // make progress
}
@@ -73,7 +72,7 @@ func (P *Parser) Expect(tok int) {
if P.tok == tok {
P.Next()
} else {
- P.Error("expected `" + Scanner.TokenName(tok) + "`, found `" + Scanner.TokenName(P.tok) + "`");
+ P.Error(P.beg, "expected '" + Scanner.TokenName(tok) + "', found '" + Scanner.TokenName(P.tok) + "'");
}
}
@@ -130,7 +129,7 @@ func (P *Parser) ParseTypeName() {
func (P *Parser) ParseType() {
P.Trace("Type");
if !P.TryType() {
- P.Error("type expected");
+ P.Error(P.beg, "type expected");
}
P.Ecart();
}
@@ -583,7 +582,7 @@ func (P *Parser) ParseControlFlowStat(tok int) {
func (P *Parser) ParseStatement() {
P.Trace("Statement");
if !P.TryStatement() {
- P.Error("statement expected");
+ P.Error(P.beg, "statement expected");
}
P.Ecart();
}
@@ -874,7 +873,7 @@ func (P *Parser) ParseDeclaration() {
case Scanner.EXPORT:
P.ParseExportDecl();
default:
- P.Error("declaration expected");
+ P.Error(P.beg, "declaration expected");
}
if indent != P.indent {
panic "imbalanced tracing code"
@@ -916,7 +915,7 @@ func (P *Parser) ParseOperand() {
case Scanner.NEW:
P.ParseNew();
default:
- P.Error("operand expected");
+ P.Error(P.beg, "operand expected");
}
P.Ecart();
}
@@ -1004,9 +1003,9 @@ func (P *Parser) ParseUnaryExpr() {
func Precedence(tok int) int {
// TODO should use a map or array here for lookup
switch tok {
- case Scanner.COR:
+ case Scanner.LOR:
return 1;
- case Scanner.CAND:
+ case Scanner.LAND:
return 2;
case Scanner.EQL, Scanner.NEQ, Scanner.LSS, Scanner.LEQ, Scanner.GTR, Scanner.GEQ:
return 3;
diff --git a/usr/gri/src/scanner.go b/usr/gri/src/scanner.go
index 7389cdac3..94d8f1915 100644
--- a/usr/gri/src/scanner.go
+++ b/usr/gri/src/scanner.go
@@ -16,7 +16,7 @@ export
SHL, SHR,
ADD_ASSIGN, SUB_ASSIGN, MUL_ASSIGN, QUO_ASSIGN, REM_ASSIGN,
AND_ASSIGN, OR_ASSIGN, XOR_ASSIGN, SHL_ASSIGN, SHR_ASSIGN,
- CAND, COR,
+ LAND, LOR,
BREAK, CASE, CHAN, CONST, CONTINUE, DEFAULT, ELSE, EXPORT, FALLTHROUGH, FALSE,
FOR, FUNC, GO, GOTO, IF, IMPORT, INTERFACE, IOTA, MAP, NEW, NIL, PACKAGE, RANGE,
RETURN, SELECT, STRUCT, SWITCH, TRUE, TYPE, VAR
@@ -81,8 +81,8 @@ const (
SHL_ASSIGN;
SHR_ASSIGN;
- CAND;
- COR;
+ LAND;
+ LOR;
// keywords
KEYWORDS_BEG;
@@ -184,8 +184,8 @@ func TokenName(tok int) string {
case SHL_ASSIGN: return "<<=";
case SHR_ASSIGN: return ">>=";
- case CAND: return "&&";
- case COR: return "||";
+ case LAND: return "&&";
+ case LOR: return "||";
case BREAK: return "break";
case CASE: return "case";
@@ -249,6 +249,10 @@ func digit_val (ch int) int {
export Scanner
type Scanner struct {
+ filename string; // error reporting only
+ nerrors int; // number of errors
+ errpos int; // last error position
+
src string;
pos int; // current reading position
ch int; // one char look-ahead
@@ -389,17 +393,25 @@ func (S *Scanner) LineCol(pos int) (line, col int) {
func (S *Scanner) Error(pos int, msg string) {
- line, col := S.LineCol(pos);
- print "error ", line, ":", col, ": ", msg, "\n";
+ const errdist = 10;
+ if pos > S.errpos + errdist || S.nerrors == 0 {
+ line, col := S.LineCol(pos);
+ print S.filename, ":", line, ":", col, ": ", msg, "\n";
+ S.nerrors++;
+ S.errpos = pos;
+ }
}
-func (S *Scanner) Open (src string) {
+func (S *Scanner) Open (filename, src string) {
if Keywords == nil {
Init();
}
- //S.nerrors = 0;
+ S.filename = filename;
+ S.nerrors = 0;
+ S.errpos = 0;
+
S.src = src;
S.pos = 0;
S.Next();
@@ -438,19 +450,18 @@ func IntString(x, base int) string {
}
-
func CharString(ch int) string {
s := string(ch);
switch ch {
- case '\a': s = "\\a";
- case '\b': s = "\\b";
- case '\f': s = "\\f";
- case '\n': s = "\\n";
- case '\r': s = "\\r";
- case '\t': s = "\\t";
- case '\v': s = "\\v";
- case '\\': s = "\\";
- case '\'': s = "\\'";
+ case '\a': s = `\a`;
+ case '\b': s = `\b`;
+ case '\f': s = `\f`;
+ case '\n': s = `\n`;
+ case '\r': s = `\r`;
+ case '\t': s = `\t`;
+ case '\v': s = `\v`;
+ case '\\': s = `\\`;
+ case '\'': s = `\'`;
}
return "'" + s + "' (U+" + IntString(ch, 16) + ")";
}
@@ -708,11 +719,10 @@ func (S *Scanner) Select4 (tok0, tok1, ch2, tok2, tok3 int) int {
func (S *Scanner) Scan () (tok, beg, end int) {
S.SkipWhitespace();
- tok = ILLEGAL;
- beg = S.pos - 1;
- end = beg;
-
ch := S.ch;
+ tok = ILLEGAL;
+ beg = S.chpos;
+
switch {
case is_letter(ch): tok = S.ScanIdentifier();
case digit_val(ch) < 10: tok = S.ScanNumber(false);
@@ -755,12 +765,13 @@ func (S *Scanner) Scan () (tok, beg, end int) {
case '>': tok = S.Select4(GTR, GEQ, '>', SHR, SHR_ASSIGN);
case '=': tok = S.Select2(ASSIGN, EQL);
case '!': tok = S.Select2(NOT, NEQ);
- case '&': tok = S.Select3(AND, AND_ASSIGN, '&', CAND);
- case '|': tok = S.Select3(OR, OR_ASSIGN, '|', COR);
+ case '&': tok = S.Select3(AND, AND_ASSIGN, '&', LAND);
+ case '|': tok = S.Select3(OR, OR_ASSIGN, '|', LOR);
+ default:
+ S.Error(beg, "illegal character " + CharString(ch));
+ tok = ILLEGAL;
}
}
- end = S.pos - 1; // TODO correct? (Unicode)
-
- return tok, beg, end;
+ return tok, beg, S.chpos;
}
diff --git a/usr/gri/src/test_parser.go b/usr/gri/src/test_parser.go
index 35d51b57a..78d8d8711 100644
--- a/usr/gri/src/test_parser.go
+++ b/usr/gri/src/test_parser.go
@@ -8,9 +8,9 @@ import Scanner "scanner"
import Parser "parser"
-func Parse(src string, verbose int) {
+func Parse(filename, src string, verbose int) {
S := new(Scanner.Scanner);
- S.Open(src);
+ S.Open(filename, src);
P := new(Parser.Parser);
P.Open(S, verbose);
@@ -31,12 +31,10 @@ func main() {
continue;
}
- var src string;
- var ok bool;
- src, ok = sys.readfile(sys.argv(i));
+ src, ok := sys.readfile(sys.argv(i));
if ok {
print "parsing " + sys.argv(i) + "\n";
- Parse(src, verbose);
+ Parse(sys.argv(i), src, verbose);
} else {
print "error: cannot read " + sys.argv(i) + "\n";
}
diff --git a/usr/gri/src/test_scanner.go b/usr/gri/src/test_scanner.go
index f43d12641..5ebff817b 100644
--- a/usr/gri/src/test_scanner.go
+++ b/usr/gri/src/test_scanner.go
@@ -7,14 +7,11 @@ package main
import Scanner "scanner"
-func Scan(src string) {
+func Scan(filename, src string) {
S := new(Scanner.Scanner);
- S.Open(src);
+ S.Open(filename, src);
for {
- //var t Scanner.Token;
- var tok, beg, end int;
- tok, beg, end = S.Scan(/*&t*/);
- //t.Print(); // TODO this doesn't compile?
+ tok, beg, end := S.Scan();
print Scanner.TokenName(tok), "\t ", src[beg : end], "\n";
if tok == Scanner.EOF {
return;
@@ -30,7 +27,7 @@ func main() {
src, ok = sys.readfile(sys.argv(i));
if ok {
print "scanning " + sys.argv(i) + "\n";
- Scan(src);
+ Scan(sys.argv(i), src);
} else {
print "error: cannot read " + sys.argv(i) + "\n";
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-29 22:34:52 +0000