Add test.throws.

src/builtins/bindings.zig

@@ -75,19 +75,7 @@ pub const Symbol = enum {
     paused,
     done,
 
-    @"error",
     float,
-    object,
-    map,
-    list,
-    function,
-    fiber,
-    string,
-    array,
-    none,
-    symbol,
-    pointer,
-    metatype,
 
     // Open modes.
     read,

src/parser.zig

@@ -900,7 +900,7 @@ pub const Parser = struct {
             .pound,
             .void_k,
             .type_k,
-            .none_k,
+            .error_k,
             .ident => {
                 return try self.parseTermExpr(.{});
             },

src/std/test.cy

@@ -12,4 +12,17 @@
 --| Returns `true` if two numbers are near each other within epsilon 1e-5.
 #host func eqNear(a any, b any) bool
 
-#host func fail() any
+func fail():
+    throw error.AssertError
+
+func fail(msg String):
+    eprint(msg)
+    throw error.AssertError
+
+--| Asserts that an error was thrown when invoking a function.
+func throws(fn any, err error):
+    var res = try fn()
+    if typeof(res) != error:
+        fail('Expected error.')
+    if res != err:
+        fail("Expected `$(err)`, found `$(res)`.")

src/std/test.zig

@@ -35,7 +35,6 @@ const funcs = [_]NameHostFunc{
     .{"eq", eq},
     .{"eqList", zErrFunc(eqList)},
     .{"eqNear", zErrFunc(eqNear)},
-    .{"fail", fail},
 };
 
 pub fn onLoad(vm_: ?*cc.VM, mod: cc.Sym) callconv(.C) void {
@@ -46,10 +45,6 @@ pub fn onLoad(vm_: ?*cc.VM, mod: cc.Sym) callconv(.C) void {
     b.declareFuncSig("erase", &.{bt.Any}, bt.Dynamic, erase) catch cy.fatal();
 }
 
-fn fail(vm: *cy.VM, _: [*]const Value, _: u8) Value {
-    return rt.prepThrowError(vm, .AssertError);
-}
-
 /// Simply returns the value so the caller get's an erased `any` type.
 fn erase(vm: *cy.VM, args: [*]const Value, _: u8) Value {
     vm.retain(args[0]);

test/core/symbols.cy

@@ -1,6 +1,6 @@
 use test
 
 var n = .Tiger
-test.eq(int(n), 63)
+test.eq(int(n), 53)
 
 --cytest: pass