conditionally unwrapping while loops

compiler/parser/parser.odin

@@ -2229,19 +2229,7 @@ parse_control_body :: proc(parser: ^Parser, header: ast.Expr_Id, diagnostic: str
 	return single
 }
 
-parse_if :: proc(parser: ^Parser) -> ast.Stmt_Id {
-	start := advance(parser) // consume 'if'
-	skip_newlines(parser)
-	saved := parser.no_struct_literal
-	parser.no_struct_literal = true
-	saved_capture_pipe := parser.capture_pipe
-	saved_if_condition := parser.if_condition
-	parser.capture_pipe = true
-	parser.if_condition = true
-	condition := parse_expression(parser)
-	parser.if_condition = saved_if_condition
-	parser.capture_pipe = saved_capture_pipe
-	parser.no_struct_literal = saved
+parse_conditional_captures :: proc(parser: ^Parser) -> ([]symbol.Id, ast.Expr_Id) {
 	captures: [dynamic]symbol.Id
 	captures.allocator = parser.module.allocator
 	guard := ast.INVALID_EXPR
@@ -2267,9 +2255,9 @@ parse_if :: proc(parser: ^Parser) -> ast.Stmt_Id {
 			if current(parser).kind == .Pipe {
 				source.add(parser.diagnostics, current(parser).span, "expected a guard expression after ':'")
 			} else {
-				saved = parser.no_struct_literal
+				saved := parser.no_struct_literal
 				parser.no_struct_literal = true
-				saved_capture_pipe = parser.capture_pipe
+				saved_capture_pipe := parser.capture_pipe
 				parser.capture_pipe = true
 				guard = parse_expression(parser)
 				parser.capture_pipe = saved_capture_pipe
@@ -2280,6 +2268,23 @@ parse_if :: proc(parser: ^Parser) -> ast.Stmt_Id {
 			source.add(parser.diagnostics, current(parser).span, "expected '|' to close unwrap captures")
 		}
 	}
+	return captures[:], guard
+}
+
+parse_if :: proc(parser: ^Parser) -> ast.Stmt_Id {
+	start := advance(parser) // consume 'if'
+	skip_newlines(parser)
+	saved := parser.no_struct_literal
+	parser.no_struct_literal = true
+	saved_capture_pipe := parser.capture_pipe
+	saved_if_condition := parser.if_condition
+	parser.capture_pipe = true
+	parser.if_condition = true
+	condition := parse_expression(parser)
+	parser.if_condition = saved_if_condition
+	parser.capture_pipe = saved_capture_pipe
+	parser.no_struct_literal = saved
+	captures, guard := parse_conditional_captures(parser)
 	then_body := parse_control_body(
 		parser,
 		condition,
@@ -2608,8 +2613,12 @@ parse_while :: proc(parser: ^Parser) -> ast.Stmt_Id {
 	skip_newlines(parser)
 	saved := parser.no_struct_literal
 	parser.no_struct_literal = true
+	saved_capture_pipe := parser.capture_pipe
+	parser.capture_pipe = true
 	condition := parse_expression(parser)
+	parser.capture_pipe = saved_capture_pipe
 	parser.no_struct_literal = saved
+	captures, guard := parse_conditional_captures(parser)
 	skip_newlines(parser)
 
 	update := ast.INVALID_STMT
@@ -2631,6 +2640,8 @@ parse_while :: proc(parser: ^Parser) -> ast.Stmt_Id {
 		span=span_from(start.span, previous(parser).span),
 		expr=condition,
 		body=body,
+		captures=captures,
+		guard=guard,
 		label=label,
 		update=update,
 		diagnostic=source.INVALID_DIAGNOSTIC,