commit 0496419

Simplify parser macros

  1@@ -5,10 +5,12 @@
  2 
  3 #include "expl.h"
  4 
  5-#define current_char(p, c) ((p)->src[(p)->pos] == (c))
  6-#define advance(p) ((p)->pos++)
  7-#define pos(p) ((p)->pos)
  8-#define peek(p) ((p)->src[(p)->pos + 1])
  9+#define current(p)    ((p)->src[(p)->pos])
 10+#define peek(p)       ((p)->src[(p)->pos + 1])
 11+#define is(p, c)      (current(p) == (c))
 12+#define end(p)        (is(p, '\0'))
 13+#define advance(p)    ((p)->pos++)
 14+#define length(p, s)  ((p)->pos - (s))
 15 
 16 typedef enum {
 17 	EXPRESSION_TYPE_ATOM,
 18@@ -98,7 +100,7 @@ static expression*
 19 parse_expression(parser* p)
 20 {
 21 	skip_space(p);
 22-	switch (p->src[p->pos]) {
 23+	switch (current(p)) {
 24 	case '"':
 25 		return value(p, EXPRESSION_TYPE_STRING);
 26 	case '(':
 27@@ -129,7 +131,7 @@ list(parser* p)
 28 	next = &node->child;
 29 
 30 	skip_space(p);
 31-	while (!current_char(p, ')') && !current_char(p, '\0')) {
 32+	while (!is(p, ')') && !end(p)) {
 33 		*next = parse_expression(p);
 34 		if (!*next) {
 35 			free_node(node);
 36@@ -140,7 +142,7 @@ list(parser* p)
 37 		skip_space(p);
 38 	}
 39 
 40-	if (current_char(p, '\0')) {
 41+	if (end(p)) {
 42 		p->err = EXPL_ERR_EXPECTED_LIST;
 43 		free_node(node);
 44 		return NULL;
 45@@ -174,7 +176,7 @@ parse(const char* source)
 46 	p.src = source;
 47 
 48 	skip_space(&p);
 49-	while (!current_char(&p, '\0')) {
 50+	while (!end(&p)) {
 51 		*next = parse_expression(&p);
 52 		if (!*next) {
 53 			free_node(head);
 54@@ -200,21 +202,21 @@ value(parser* p, expression_type type)
 55 	start = p->pos;
 56 
 57 	if (type == EXPRESSION_TYPE_STRING) {
 58-		while (!current_char(p, '"') && !current_char(p, '\0')) {
 59-			if (current_char(p, '\\') && p->src[p->pos + 1])
 60+		while (!is(p, '"') && !end(p)) {
 61+			if (is(p, '\\') && peek(p))
 62 				advance(p);
 63 			advance(p);
 64 		}
 65 
 66-		if (current_char(p, '\0')) {
 67+		if (end(p)) {
 68 			p->err = EXPL_ERR_EXPECTED_STRING;
 69 			return NULL;
 70 		}
 71 	}
 72 	else {
 73-		while (p->src[p->pos] &&
 74-		       !strchr("();\"", p->src[p->pos]) &&
 75-		       !isspace((unsigned char)p->src[p->pos]))
 76+		while (!end(p) &&
 77+		       !strchr("();\"", current(p)) &&
 78+		       !isspace((unsigned char)current(p)))
 79 			advance(p);
 80 	}
 81 
 82@@ -229,7 +231,7 @@ value(parser* p, expression_type type)
 83 		return NULL;
 84 	}
 85 
 86-	node->value = _strndup(p->src + start, p->pos - start);
 87+	node->value = _strndup(p->src + start, length(p, start));
 88 	if (!node->value) {
 89 		free_node(node);
 90 		p->err = EXPL_ERR_OUT_OF_MEMORY;
 91@@ -418,10 +420,10 @@ register_native(environment** env, const char* name, expl_native fn, void* data)
 92 static void
 93 skip_space(parser* p)
 94 {
 95-	while (isspace((unsigned char)p->src[p->pos]) || current_char(p, ';')) {
 96+	while (isspace((unsigned char)current(p)) || is(p, ';')) {
 97 		/* comment */
 98-		if (current_char(p, ';')) {
 99-			while (!current_char(p, '\n') && !current_char(p, '\0'))
100+		if (is(p, ';')) {
101+			while (!is(p, '\n') && !end(p))
102 				advance(p);
103 		}
104