hare

commit 0f219a2173222ad8dc113e68df557daf82aebeaa
parent 607eb193e4f36252debbf1507d81efe0b51636b8
Author: Drew DeVault <sir@cmpwn.com>
Date:   Wed, 24 Feb 2021 09:26:48 -0500

main.ha: accept a file name as input

Diffstat:
M
main.ha
 | 
16
+++++++++++++++-

1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/main.ha b/main.ha
@@ -4,7 +4,21 @@ use io;
 use os;
 
 export fn main() void = {
-	let lexer = lex::lexer_init(os::stdin, "<stdin>");
+	let in: (*io::stream, str) = switch (len(os::args)) {
+		1 => (os::stdin, "<stdin>"),
+		2 => {
+			let fd = match (os::open(os::args[1])) {
+				err: io::error => fmt::fatal("Error opening '{}': {}",
+					os::args[1], io::errstr(err)),
+				fd: *io::stream => fd,
+			};
+			(fd, os::args[1]);
+		},
+		* => fmt::fatal("Usage: {} [<input>]", os::args[0]),
+	};
+	defer io::close(in.0);
+	let lexer = lex::lexer_init(in.0, in.1);
+
 	for (true) match (lex::lex(&lexer)) {
 		t: (lex::token, lex::location) => {
 			let tok = t.0, loc = t.1;