Add `intrinsics.concatenate`

1 files changed, 86 insertions, 0 deletions

diff --git a/src/check_builtin.cpp b/src/check_builtin.cpp
index a19fb15ec..13a1c4e69 100644
--- a/src/check_builtin.cpp
+++ b/src/check_builtin.cpp
@@ -4885,6 +4885,92 @@ gb_internal bool check_builtin_procedure(CheckerContext *c, Operand *operand, As
 		break;
 	}
 
+	case BuiltinProc_concatenate: {
+		Operand lhs = {};
+		Operand rhs = {};
+
+		check_expr(c, &lhs, ce->args[0]);
+		if (lhs.mode == Addressing_Invalid) {
+			return false;
+		}
+		check_expr(c, &rhs, ce->args[1]);
+		if (rhs.mode == Addressing_Invalid) {
+			return false;
+		}
+		if (lhs.mode != Addressing_Constant) {
+			error(lhs.expr, "'%*.s' expects a constant array or slice", LIT(builtin_name));
+			return false;
+		}
+		if (rhs.mode != Addressing_Constant) {
+			error(rhs.expr, "'%*.s' expects a constant array or slice", LIT(builtin_name));
+			return false;
+		}
+
+		if (!are_types_identical(lhs.type, rhs.type)) {
+			gbString a = type_to_string(lhs.type);
+			gbString b = type_to_string(rhs.type);
+			error(rhs.expr, "'%*.s' expects a two constant values of the same type, got '%s' vs '%s'", LIT(builtin_name), a, b);
+			gb_string_free(b);
+			gb_string_free(a);
+			return false;
+		}
+
+		if (!is_type_slice(lhs.type) && !is_type_array(lhs.type)) {
+			gbString a = type_to_string(lhs.type);
+			error(lhs.expr, "'%*.s' expects a constant array or slice, got %s", LIT(builtin_name), a);
+			gb_string_free(a);
+			return false;
+		}
+
+		if (lhs.value.kind != ExactValue_Compound) {
+			gbString a = exact_value_to_string(lhs.value);
+			error(lhs.expr, "Expected a compound literal value for '%.*s', got '%s'", LIT(builtin_name), a);
+			gb_string_free(a);
+			return false;
+		}
+		if (rhs.value.kind != ExactValue_Compound) {
+			gbString a = exact_value_to_string(rhs.value);
+			error(rhs.expr, "Expected a compound literal value for '%.*s', got '%s'", LIT(builtin_name), a);
+			gb_string_free(a);
+			return false;
+		}
+
+		ast_node(lhs_cl, CompoundLit, lhs.value.value_compound);
+		ast_node(rhs_cl, CompoundLit, rhs.value.value_compound);
+
+		for (Ast *elem : lhs_cl->elems) {
+			if (elem->kind == Ast_FieldValue) {
+				error(elem, "'%.*s' does not allow the use of 'field = value' to be concatenated together", LIT(builtin_name));
+				return false;
+			}
+		}
+		for (Ast *elem : rhs_cl->elems) {
+			if (elem->kind == Ast_FieldValue) {
+				error(elem, "'%.*s' does not allow the use of 'field = value' to be concatenated together", LIT(builtin_name));
+				return false;
+			}
+		}
+
+		Ast *type_ast = lhs_cl->type;
+		if (type_ast == nullptr) {
+			type_ast = rhs_cl->type;
+		}
+
+
+		Array<Ast *> new_elems = {};
+		array_init(&new_elems, heap_allocator());
+
+		array_add_elems(&new_elems, lhs_cl->elems.data, lhs_cl->elems.count);
+		array_add_elems(&new_elems, rhs_cl->elems.data, rhs_cl->elems.count);
+
+		Ast *new_compound_lit = ast_compound_lit(lhs.expr->file(), type_ast, new_elems, ast_token(lhs.expr), ast_end_token(rhs.expr));
+
+		operand->mode  = Addressing_Constant;
+		operand->value = exact_value_compound(new_compound_lit);
+		operand->type  = lhs.type;
+		break;
+	}
+
 	case BuiltinProc_alloca:
 		{
 			Operand sz = {};