hare

commit a8ea19b4793d0332b5af65e2e7425dc5092313b7
parent 6a0d142c181d2f1601c6f4f991d0f75c265cc871
Author: Alexey Yerin <yyp@disroot.org>
Date:   Sun, 18 Apr 2021 21:53:38 +0300

hare/parse,unparse: add support for len expression

Diffstat:
M
hare/parse/+test/expr.ha
 | 
1
+
M
hare/parse/expr.ha
 | 
18
+++++++++++++++++-
M
hare/unparse/expr.ha
 | 
6
+++++-

3 files changed, 23 insertions(+), 2 deletions(-)
diff --git a/hare/parse/+test/expr.ha b/hare/parse/+test/expr.ha
@@ -42,6 +42,7 @@
 	delete(x[10..20]);
 	delete(x[..]);
 	free(x);
+	len([1, 2, 3, 4]);
 };
 ");
 };
diff --git a/hare/parse/expr.ha b/hare/parse/expr.ha
@@ -136,6 +136,22 @@ fn append_expr(lexer: *lex::lexer) (ast::expr | error) = {
 	};
 };
 
+fn measurement(lexer: *lex::lexer) (ast::expr | error) = {
+	let tok = want(lexer, ltok::LEN, ltok::SIZE, ltok::OFFSET)?;
+
+	return switch (tok.0) {
+		ltok::LEN => {
+			want(lexer, ltok::LPAREN)?;
+			let e = expression(lexer)?;
+			want(lexer, ltok::RPAREN)?;
+
+			alloc(e): ast::len_expr;
+		},
+		ltok::SIZE => abort(), // TODO
+		ltok::OFFSET => abort(), // TODO
+	};
+};
+
 fn binarithm(
 	lexer: *lex::lexer,
 	lvalue: (ast::expr | void),
@@ -234,7 +250,7 @@ fn builtin(lexer: *lex::lexer) (ast::expr | error) = {
 				* => abort(),
 			};
 		},
-		ltok::SIZE, ltok::LEN, ltok::OFFSET => abort(), // TODO
+		ltok::SIZE, ltok::LEN, ltok::OFFSET => measurement(lexer)?,
 		ltok::DEFER => {
 			want(lexer, ltok::DEFER)?;
 			alloc(expression(lexer)?): ast::defer_expr;
diff --git a/hare/unparse/expr.ha b/hare/unparse/expr.ha
@@ -220,7 +220,11 @@ export fn expr(
 			z;
 		},
 		e: ast::match_expr => abort(),
-		e: ast::len_expr => abort(),
+		e: ast::len_expr => {
+			let z = fmt::fprint(out, "len(")?;
+			z += expr(out, indent, *e)?;
+			z + fmt::fprint(out, ")")?;
+		},
 		e: ast::size_expr => abort(),
 		e: ast::offset_expr => abort(),
 		e: ast::propagate_expr => {