hlc

commit d5d9ba503bddab9fd6da4d1b06ebbdad85d09ea2
parent 75b1868517b633d8dec332fefc4ae697539687ba
Author: thing1 <l.standen@posteo.com>
Date:   Tue,  7 Oct 2025 13:21:57 +0100

added addtional lexers

Diffstat:
M
lex.c
 | 
61
++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----
M
spec.md
 | 
4
++++

2 files changed, 60 insertions(+), 5 deletions(-)
diff --git a/lex.c b/lex.c
@@ -35,6 +35,14 @@ peekc(FILE *in) {
 }
 
 lex_val *
+lex_char(char c, lex_type t) {
+	if (getchr(input) != c) return &lex_error;
+	lv.type = t;
+	lv.data = NULL;
+	return &lv;
+}
+
+lex_val *
 lex_type(void) {
 	switch (peekc(input)) {
 	case 'b': 
@@ -60,6 +68,51 @@ lex_type(void) {
 	return &lv;
 }
 
+
+
+lex_val *
+lex_comma() {
+	return lex_char(',', COMMA);
+}
+
+lex_val *
+lex_semi() {
+	return lex_char(';', SEMI);
+}
+
+lex_val *
+lex_assign() {
+	return lex_char('=', ASSIGN);
+}
+
+lex_val *
+lex_sym() {
+	switch (getchr(input)) {
+	case '<': 
+		switch (peekc(input)) {
+		case '=': getchr(input); lv.type = LTE; break;
+		default: lv.type = LT; break;
+		}
+		return lv;
+	case '>': 
+		switch (peekc(input)) {
+		case '=': getchr(input); lv.type = GTE; break;
+		default: lv.type = GT; break;
+		}
+		return lv;
+	case '!': 
+		lv.type = LT; break;
+	case '+': lv.type = LT; break; 
+	case '-': lv.type = LT; break;
+	case '/': lv.type = LT; break;
+	case '*': lv.type = LT; break;
+	case '&': lv.type = LT; break; 
+	}
+}
+
+
+
+/* TODO: make this execpt pointer derefs at the start of a name */
 lex_val *
 lex_name(void) {
 	static char name[32] = { 0 };
@@ -72,10 +125,9 @@ lex_name(void) {
 	lv.data = name;
 	lv.type = NAME;
 
-	/*
 	switch (peekc(input)) {
-	case '=': nextfn = &lex_assign; break; CHECK FOR == and =
-	case ',': nextfn = &lex_comma; break;
+	case '=': nextfn = &lex_assign; break; /* CHECK FOR == and = */
+	case ',': nextfn = &lex_comma; break; /* leads to lex_type */
 	case ';': nextfn = &lex_semi; break;
 
 	case '<':
@@ -84,13 +136,12 @@ lex_name(void) {
 	case '+': 
 	case '-':
 	case '/': 
-	case '*': CHECK FOR MUL AND PTR
+	case '*': /* CHECK FOR MUL AND PTR */
 	case '&':
 		  nextfn = &lex_sym; break;
 		  break;
 	default: return &lex_error;
 	}
-	*/
 
 	return &lv;
 }
diff --git a/spec.md b/spec.md
@@ -45,6 +45,7 @@ The syntax for the language can be defined in the following BNF notation
 
     expr    ::= NUM
             ||= '"' STRING '"'
+            ||= var
             ||= dec
             ||= expr '+' expr
             ||= expr '-' expr 
@@ -58,3 +59,6 @@ The syntax for the language can be defined in the following BNF notation
             ||= expr '<=' expr 
             ||= '*' expr
             ||= '&' expr
+            
+    var     ::= NAME
+            || '*' var