From e22afe5424a2c869cd2b321c70cc23dcec9433b7 Mon Sep 17 00:00:00 2001
From: Christoffer Lerno <christoffer@aegik.com>
Date: Sun, 13 Aug 2023 18:15:20 +0200
Subject: [PATCH] Allow "if (try foo())"."

---
 src/compiler/llvm_codegen_expr.c    | 11 ++++++-
 src/compiler/sema_stmts.c           |  8 +++--
 src/version.h                       |  2 +-
 test/test_suite/errors/try_expr.c3t | 49 +++++++++++++++++++++++++++++
 4 files changed, 66 insertions(+), 4 deletions(-)
 create mode 100644 test/test_suite/errors/try_expr.c3t

diff --git a/src/compiler/llvm_codegen_expr.c b/src/compiler/llvm_codegen_expr.c
index 6d24ada74..b1a52c035 100644
--- a/src/compiler/llvm_codegen_expr.c
+++ b/src/compiler/llvm_codegen_expr.c
@@ -6168,7 +6168,16 @@ static inline void llvm_emit_try_unwrap(GenContext *c, BEValue *value, Expr *exp
 	BEValue addr;
 	if (expr->try_unwrap_expr.assign_existing)
 	{
-		llvm_emit_expr(c, &addr, expr->try_unwrap_expr.lhs);
+		Expr *lhs = expr->try_unwrap_expr.lhs;
+		if (lhs)
+		{
+			llvm_emit_expr(c, &addr, lhs);
+		}
+		else
+		{
+			llvm_emit_try_assign_try_catch(c, true, value, NULL, NULL, expr->try_unwrap_expr.optional);
+			return;
+		}
 	}
 	else
 	{
diff --git a/src/compiler/sema_stmts.c b/src/compiler/sema_stmts.c
index 271a09558..f04122b3a 100644
--- a/src/compiler/sema_stmts.c
+++ b/src/compiler/sema_stmts.c
@@ -534,10 +534,14 @@ static inline bool sema_analyse_try_unwrap(SemaContext *context, Expr *expr)
 	if (!optional)
 	{
 		if (!sema_analyse_expr(context, ident)) return false;
+		// The `try foo()` case.
 		if (ident->expr_kind != EXPR_IDENTIFIER)
 		{
-			SEMA_ERROR(ident, "Only single identifiers may be unwrapped using 'try var', maybe you wanted 'try (expr)' instead?");
-			return false;
+			expr->try_unwrap_expr.optional = ident;
+			expr->try_unwrap_expr.lhs = NULL;
+			expr->try_unwrap_expr.assign_existing = true;
+			expr->type = type_bool;
+			return true;
 		}
 		Decl *decl = ident->identifier_expr.decl;
 		if (decl->decl_kind != DECL_VAR)
diff --git a/src/version.h b/src/version.h
index 07bbc889e..0111e7739 100644
--- a/src/version.h
+++ b/src/version.h
@@ -1 +1 @@
-#define COMPILER_VERSION "0.4.605"
\ No newline at end of file
+#define COMPILER_VERSION "0.4.606"
\ No newline at end of file
diff --git a/test/test_suite/errors/try_expr.c3t b/test/test_suite/errors/try_expr.c3t
new file mode 100644
index 000000000..9ca8de6f2
--- /dev/null
+++ b/test/test_suite/errors/try_expr.c3t
@@ -0,0 +1,49 @@
+// #target: macos-x64
+module foo;
+import std::io;
+
+fn void main()
+{
+	int a;
+	if (try foo())
+	{
+		a--;
+	}
+	else
+	{
+		a++;
+	}
+}
+
+fn void! foo() {}
+
+/* #expect: foo.ll
+
+define void @foo.main() #0 {
+entry:
+  %a = alloca i32, align 4
+  store i32 0, ptr %a, align 4
+  %0 = call i64 @foo.foo()
+  %not_err = icmp eq i64 %0, 0
+  %1 = call i1 @llvm.expect.i1(i1 %not_err, i1 true)
+  br i1 %1, label %after_check, label %catch_landing
+after_check:                                      ; preds = %entry
+  br label %phi_try_catch
+catch_landing:                                    ; preds = %entry
+  br label %phi_try_catch
+phi_try_catch:                                    ; preds = %catch_landing, %after_check
+  %val = phi i1 [ true, %after_check ], [ false, %catch_landing ]
+  br i1 %val, label %if.then, label %if.else
+if.then:                                          ; preds = %phi_try_catch
+  %2 = load i32, ptr %a, align 4
+  %sub = sub i32 %2, 1
+  store i32 %sub, ptr %a, align 4
+  br label %if.exit
+if.else:                                          ; preds = %phi_try_catch
+  %3 = load i32, ptr %a, align 4
+  %add = add i32 %3, 1
+  store i32 %add, ptr %a, align 4
+  br label %if.exit
+if.exit:                                          ; preds = %if.else, %if.then
+  ret void
+}