harec

commit 9048ce748f804c96ea61d27b2139edd8d4548428
parent 171bc0b0d1d5940b779ccab776bca38d4a59f639
Author: Sudipto Mallick <smlckz@disroot.org>
Date:   Tue, 13 Apr 2021 12:56:23 +0000

lex: allow signed exponents for floating literals

Diffstat:
M
src/lex.c
 | 
33
+++++++++++++++++++++++++--------
M
tests/00-constants.ha
 | 
1
+

2 files changed, 26 insertions(+), 8 deletions(-)
diff --git a/src/lex.c b/src/lex.c
@@ -304,7 +304,7 @@ lex_literal(struct lexer *lexer, struct token *out)
 		if (!strchr(basechrs, c)) {
 			switch (c) {
 			case '.':
-				if (isfloat || suff) {
+				if (isfloat || suff || exp) {
 					push(lexer, c, true);
 					goto finalize;
 				}
@@ -322,7 +322,15 @@ lex_literal(struct lexer *lexer, struct token *out)
 					push(lexer, c, true);
 					goto finalize;
 				}
-				exp = &lexer->buf[lexer->buflen];
+				// exponent is always in base 10
+				basechrs = "0123456789";
+				c = next(lexer, NULL, true);
+				if (c != '-' && c != '+' && !strchr(basechrs, c)) {
+					push(lexer, c, true);
+					push(lexer, 'e', true);
+					goto finalize;
+				};
+				exp = &lexer->buf[lexer->buflen - 1];
 				break;
 			case 'i':
 			case 'u':
@@ -382,11 +390,20 @@ finalize:
 		}
 	}
 
-	uintmax_t exponent = 0;
+	intmax_t exponent = 0;
 	if (exp) {
 		char *endptr = NULL;
-		exponent = strtoumax(exp, &endptr, 10);
-		if (endptr == exp) {
+		exponent = strtoimax(exp, &endptr, 10);
+		// integers can't have negative exponents
+		if (exponent < 0 && !suff) {
+			out->storage = STORAGE_FCONST;
+		}
+		enum type_storage s = out->storage;
+		bool valid = exponent >= 0
+			|| s == STORAGE_F32
+			|| s == STORAGE_F64
+			|| s == STORAGE_FCONST;
+		if (endptr == exp || !valid) {
 			out->token = T_ERROR;
 			consume(lexer, -1);
 			return out->token;
@@ -402,14 +419,14 @@ finalize:
 	case STORAGE_U64:
 	case STORAGE_SIZE:
 		out->uval = strtoumax(lexer->buf, NULL, base);
-		for (uintmax_t i = 0; i < exponent; i++) {
+		for (intmax_t i = 0; i < exponent; i++) {
 			out->uval *= 10;
 		}
 		break;
 	case STORAGE_ICONST:
 		if (lexer->buf[0] != '-') {
 			uintmax_t uval = strtoumax(lexer->buf, NULL, base);
-			for (uintmax_t i = 0; i < exponent; i++) {
+			for (intmax_t i = 0; i < exponent; i++) {
 				uval *= 10;
 			}
 			if (uval > (uintmax_t)INT64_MAX) {
@@ -425,7 +442,7 @@ finalize:
 	case STORAGE_INT:
 	case STORAGE_I64:
 		out->ival = strtoimax(lexer->buf, NULL, base);
-		for (uintmax_t i = 0; i < exponent; i++) {
+		for (intmax_t i = 0; i < exponent; i++) {
 			out->ival *= 10;
 		}
 		break;
diff --git a/tests/00-constants.ha b/tests/00-constants.ha
@@ -8,4 +8,5 @@ export fn main() void = {
 		r6 = '\b', r7 = '\f', r8 = '\n', r9 = '\r', r10 = '\t',
 		r11 = '\v', r12 = '\\', r13 = '\'', r14 = '\"';
 	let f1 = 1.0, f2 = 1f32, f3 = 1.0e2, f4 = 1.0f64;
+	let f5 = 1.23e+45, f6 = 9.87e-65, f7 = 1e-7;
 };