feat: allow empty argument list methods in calls, definitions, and docs

- Compile empty `()` as a valid method signature distinct from no parentheses
- Update `call()`, `clear()`, `run()`, `try()`, and `yield()` to use empty argument lists
- Revise documentation across multiple files to reflect new signature semantics

test/assignment/local.wren

@@ -7,4 +7,4 @@ new Fn {
 
   IO.print(a = "arg") // expect: arg
   IO.print(a) // expect: arg
-}.call
+}.call()

test/break/closure_in_for.wren

@@ -5,5 +5,5 @@ for (i in [1, 2, 3]) {
   break
 }
 
-f.call
+f.call()
 // expect: 5

test/break/closure_in_while.wren

@@ -5,5 +5,5 @@ while (true) {
   break
 }
 
-f.call
+f.call()
 // expect: i

test/closure/assign_to_closure.wren

@@ -16,10 +16,10 @@ var g = null
   }
 }
 
-f.call
+f.call()
 // expect: local
 // expect: after f
 
-g.call
+g.call()
 // expect: after f
 // expect: after g

test/closure/close_over_function_parameter.wren

@@ -6,4 +6,4 @@ new Fn {|param|
   }
 }.call("param")
 
-f.call // expect: param
+f.call() // expect: param

test/closure/close_over_later_variable.wren

@@ -9,5 +9,5 @@ new Fn {
   new Fn {
     IO.print(b) // expect: b
     IO.print(a) // expect: a
-  }.call
-}.call
+  }.call()
+}.call()

test/closure/close_over_method_parameter.wren

@@ -9,4 +9,4 @@ class Foo {
 }
 
 (new Foo).method("param")
-F.call // expect: param
+F.call() // expect: param

test/closure/closed_closure_in_function.wren

@@ -7,4 +7,4 @@ var f = null
   }
 }
 
-f.call // expect: local
+f.call() // expect: local

test/closure/nested_closure.wren

@@ -11,11 +11,11 @@ new Fn {
         IO.print(b)
         IO.print(c)
       }
-    }.call
-  }.call
-}.call
+    }.call()
+  }.call()
+}.call()
 
-f.call
+f.call()
 // expect: a
 // expect: b
 // expect: c

test/closure/open_closure_in_function.wren

@@ -2,5 +2,5 @@
   var local = "local"
   new Fn {
     IO.print(local) // expect: local
-  }.call
+  }.call()
 }

test/closure/reference_closure_multiple_times.wren

@@ -8,6 +8,6 @@ var f = null
   }
 }
 
-f.call
+f.call()
 // expect: a
 // expect: a

test/closure/reuse_closure_slot.wren

@@ -10,7 +10,7 @@
     // Since a is out of scope, the local slot will be reused by b. Make sure
     // that f still closes over a.
     var b = "b"
-    f.call // expect: a
+    f.call() // expect: a
   }
 }
 

test/closure/shadow_closure_with_local.wren

@@ -7,5 +7,5 @@
       IO.print(foo) // expect: shadow
     }
     IO.print(foo) // expect: closure
-  }.call
+  }.call()
 }

test/fiber/abort.wren

@@ -2,6 +2,6 @@ var fiber = new Fiber {
   Fiber.abort("Error message.")
 }
 
-IO.print(fiber.try) // expect: Error message.
+IO.print(fiber.try()) // expect: Error message.
 IO.print(fiber.isDone) // expect: true
 IO.print(fiber.error) // expect: Error message.

test/fiber/call.wren

@@ -3,5 +3,5 @@ var fiber = new Fiber {
 }
 
 IO.print("before") // expect: before
-fiber.call         // expect: fiber
+fiber.call()       // expect: fiber
 IO.print("after")  // expect: after

test/fiber/call_direct_reenter.wren

@@ -1,7 +1,7 @@
 var fiber
 
 fiber = new Fiber {
-  fiber.call // expect runtime error: Fiber has already been called.
+  fiber.call() // expect runtime error: Fiber has already been called.
 }
 
-fiber.call
+fiber.call()

test/fiber/call_indirect_reenter.wren

@@ -2,11 +2,11 @@ var a
 var b
 
 a = new Fiber {
-  b.call // expect runtime error: Fiber has already been called.
+  b.call() // expect runtime error: Fiber has already been called.
 }
 
 b = new Fiber {
-  a.call
+  a.call()
 }
 
-b.call
+b.call()

test/fiber/call_return_implicit_null.wren

@@ -2,5 +2,5 @@ var fiber = new Fiber {
   IO.print("fiber")
 }
 
-var result = fiber.call // expect: fiber
-IO.print(result)        // expect: null
+var result = fiber.call() // expect: fiber
+IO.print(result)          // expect: null

test/fiber/call_return_value.wren

@@ -3,5 +3,5 @@ var fiber = new Fiber {
   return "result"
 }
 
-var result = fiber.call // expect: fiber
-IO.print(result)        // expect: result
+var result = fiber.call() // expect: fiber
+IO.print(result)          // expect: result

test/fiber/call_when_done.wren

@@ -2,5 +2,5 @@ var fiber = new Fiber {
   IO.print("call")
 }
 
-fiber.call // expect: call
-fiber.call // expect runtime error: Cannot call a finished fiber.
+fiber.call() // expect: call
+fiber.call() // expect runtime error: Cannot call a finished fiber.

test/fiber/closure.wren

@@ -5,9 +5,9 @@ var closure
   var a = "before"
   fiber = new Fiber {
     IO.print(a)
-    Fiber.yield
+    Fiber.yield()
     a = "after"
-    Fiber.yield
+    Fiber.yield()
     IO.print(a)
     a = "final"
   }
@@ -17,9 +17,9 @@ var closure
   }
 }
 
-fiber.call   // expect: before
-closure.call // expect: before
-fiber.call
-closure.call // expect: after
-fiber.call   // expect: after
-closure.call // expect: final
+fiber.call()   // expect: before
+closure.call() // expect: before
+fiber.call()
+closure.call() // expect: after
+fiber.call()   // expect: after
+closure.call() // expect: final

test/fiber/error.wren

@@ -3,5 +3,5 @@ var fiber = new Fiber {
 }
 
 IO.print(fiber.error) // expect: null
-IO.print(fiber.try)   // expect: String does not implement 'unknown'.
+IO.print(fiber.try()) // expect: String does not implement 'unknown'.
 IO.print(fiber.error) // expect: String does not implement 'unknown'.

test/fiber/is_done.wren

@@ -1,11 +1,11 @@
 var fiber = new Fiber {
   IO.print("1")
-  Fiber.yield
+  Fiber.yield()
   IO.print("2")
 }
 
 IO.print(fiber.isDone)  // expect: false
-fiber.call              // expect: 1
+fiber.call()            // expect: 1
 IO.print(fiber.isDone)  // expect: false
-fiber.call              // expect: 2
+fiber.call()            // expect: 2
 IO.print(fiber.isDone)  // expect: true

test/fiber/is_done_after_error.wren

@@ -2,5 +2,5 @@ var fiber = new Fiber {
   "s".unknown
 }
 
-fiber.try
+fiber.try()
 IO.print(fiber.isDone) // expect: true

test/fiber/resume_caller.wren

@@ -4,12 +4,12 @@ var b = new Fiber {
 
 var a = new Fiber {
   IO.print("begin fiber a")
-  b.call
+  b.call()
   IO.print("end fiber a")
 }
 
 IO.print("begin main")
-a.call
+a.call()
 IO.print("end main")
 
 // expect: begin main

test/fiber/run.wren

@@ -3,7 +3,7 @@ var fiber = new Fiber {
 }
 
 IO.print("before") // expect: before
-fiber.run          // expect: fiber
+fiber.run()        // expect: fiber
 
 // This does not get run since we exit when the run fiber completes.
 IO.print("nope")

test/fiber/run_direct_reenter.wren

@@ -2,9 +2,9 @@ var fiber
 
 fiber = new Fiber {
   IO.print(1) // expect: 1
-  fiber.run
+  fiber.run()
   IO.print(2) // expect: 2
 }
 
-fiber.call
+fiber.call()
 IO.print(3) // expect: 3

test/fiber/run_indirect_reenter.wren

@@ -3,17 +3,17 @@ var b
 
 a = new Fiber {
   IO.print(2)
-  b.run
+  b.run()
   IO.print("nope")
 }
 
 b = new Fiber {
   IO.print(1)
-  a.run
+  a.run()
   IO.print(3)
 }
 
-b.call
+b.call()
 // expect: 1
 // expect: 2
 // expect: 3

test/fiber/run_when_done.wren

@@ -5,9 +5,9 @@ var a = new Fiber {
 // Run a through an intermediate fiber since it will get discarded and we need
 // to return to the main one after a completes.
 var b = new Fiber {
-  a.run
+  a.run()
   IO.print("nope")
 }
 
-b.call // expect: run
-a.run // expect runtime error: Cannot run a finished fiber.
+b.call() // expect: run
+a.run()  // expect runtime error: Cannot run a finished fiber.

test/fiber/run_with_value_direct_reenter.wren

@@ -6,5 +6,5 @@ fiber = new Fiber {
   IO.print(2) // expect: 2
 }
 
-fiber.call
+fiber.call()
 IO.print(3) // expect: 3

test/fiber/run_with_value_indirect_reenter.wren

@@ -13,7 +13,7 @@ b = new Fiber {
   IO.print(3)
 }
 
-b.call
+b.call()
 // expect: 1
 // expect: 2
 // expect: 3

test/fiber/try.wren

@@ -4,7 +4,7 @@ var fiber = new Fiber {
   IO.print("after")
 }
 
-IO.print(fiber.try)
+IO.print(fiber.try())
 // expect: before
 // expect: Bool does not implement 'unknownMethod'.
 IO.print("after try") // expect: after try

test/fiber/try_direct_reenter.wren

@@ -1,7 +1,7 @@
 var fiber
 
 fiber = new Fiber {
-  fiber.try // expect runtime error: Fiber has already been called.
+  fiber.try() // expect runtime error: Fiber has already been called.
 }
 
-fiber.call
+fiber.call()

test/fiber/try_indirect_reenter.wren

@@ -2,11 +2,11 @@ var a
 var b
 
 a = new Fiber {
-  b.try // expect runtime error: Fiber has already been called.
+  b.try() // expect runtime error: Fiber has already been called.
 }
 
 b = new Fiber {
-  a.call
+  a.call()
 }
 
-b.call
+b.call()

test/fiber/try_when_done.wren

@@ -2,5 +2,5 @@ var fiber = new Fiber {
   IO.print("try")
 }
 
-fiber.try // expect: try
-fiber.try // expect runtime error: Cannot try a finished fiber.
+fiber.try() // expect: try
+fiber.try() // expect runtime error: Cannot try a finished fiber.

test/fiber/try_without_error.wren

@@ -2,7 +2,7 @@ var fiber = new Fiber {
   IO.print("fiber")
 }
 
-IO.print("before")  // expect: before
-IO.print(fiber.try) // expect: fiber
-                    // expect: null
-IO.print("after")   // expect: after
+IO.print("before")    // expect: before
+IO.print(fiber.try()) // expect: fiber
+                      // expect: null
+IO.print("after")     // expect: after

test/fiber/yield.wren

@@ -1,14 +1,14 @@
 var fiber = new Fiber {
   IO.print("fiber 1")
-  Fiber.yield
+  Fiber.yield()
   IO.print("fiber 2")
-  Fiber.yield
+  Fiber.yield()
   IO.print("fiber 3")
 }
 
-var result = fiber.call // expect: fiber 1
-IO.print("main 1")  // expect: main 1
-result = fiber.call // expect: fiber 2
-IO.print("main 2")  // expect: main 2
-result = fiber.call // expect: fiber 3
-IO.print("main 3")  // expect: main 3
+var result = fiber.call() // expect: fiber 1
+IO.print("main 1")    // expect: main 1
+result = fiber.call() // expect: fiber 2
+IO.print("main 2")    // expect: main 2
+result = fiber.call() // expect: fiber 3
+IO.print("main 3")    // expect: main 3

test/fiber/yield_from_main.wren

@@ -1 +1 @@
-Fiber.yield // expect runtime error: No fiber to yield to.
+Fiber.yield() // expect runtime error: No fiber to yield to.

test/fiber/yield_return_call_value.wren

@@ -1,14 +1,14 @@
 var fiber = new Fiber {
   IO.print("fiber 1")
-  var result = Fiber.yield
+  var result = Fiber.yield()
   IO.print(result)
-  result = Fiber.yield
+  result = Fiber.yield()
   IO.print(result)
 }
 
-fiber.call // expect: fiber 1
+fiber.call() // expect: fiber 1
 IO.print("main 1") // expect: main 1
 fiber.call("call 1") // expect: call 1
 IO.print("main 2") // expect: main 2
-fiber.call // expect: null
+fiber.call() // expect: null
 IO.print("main 3") // expect: main 3

test/fiber/yield_return_run_value.wren

@@ -1,10 +1,10 @@
 var fiber = new Fiber {
   IO.print("fiber")
-  var result = Fiber.yield
+  var result = Fiber.yield()
   IO.print(result)
 }
 
-fiber.call // expect: fiber
+fiber.call() // expect: fiber
 IO.print("main") // expect: main
 fiber.run("run") // expect: run
 

test/fiber/yield_with_no_caller.wren

@@ -1,9 +1,9 @@
 var a = new Fiber {
-  Fiber.yield // expect runtime error: No fiber to yield to.
+  Fiber.yield() // expect runtime error: No fiber to yield to.
 }
 
 // Run a chain of fibers. Since none of them are called, they all get discarded
 // and there is no remaining caller.
-var b = new Fiber { a.run }
-var c = new Fiber { b.run }
-c.run
+var b = new Fiber { a.run() }
+var c = new Fiber { b.run() }
+c.run()

test/fiber/yield_with_value.wren

@@ -6,9 +6,9 @@ var fiber = new Fiber {
   IO.print("fiber 3")
 }
 
-var result = fiber.call // expect: fiber 1
+var result = fiber.call() // expect: fiber 1
 IO.print(result) // expect: yield 1
-result = fiber.call // expect: fiber 2
+result = fiber.call() // expect: fiber 2
 IO.print(result) // expect: yield 2
-result = fiber.call // expect: fiber 3
+result = fiber.call() // expect: fiber 3
 IO.print(result) // expect: null

test/fiber/yield_with_value_with_no_caller.wren

@@ -4,6 +4,6 @@ var a = new Fiber {
 
 // Run a chain of fibers. Since none of them are called, they all get discarded
 // and there is no remaining caller.
-var b = new Fiber { a.run }
-var c = new Fiber { b.run }
-c.run
+var b = new Fiber { a.run() }
+var c = new Fiber { b.run() }
+c.run()

test/field/closure.wren

@@ -11,6 +11,6 @@ class Foo {
 }
 
 var foo = new Foo
-IO.print(foo.closeOverGet.call) // expect: Foo field
-foo.closeOverSet.call
-IO.print(foo.closeOverGet.call) // expect: new value
+IO.print(foo.closeOverGet.call()) // expect: Foo field
+foo.closeOverSet.call()
+IO.print(foo.closeOverGet.call()) // expect: new value

test/for/close_over_loop_variable.wren

@@ -4,7 +4,7 @@ for (i in [1, 2, 3]) {
   list.add(new Fn { IO.print(i) })
 }
 
-for (f in list) f.call
+for (f in list) f.call()
 // expect: 1
 // expect: 2
 // expect: 3

test/for/closure_in_body.wren

@@ -5,7 +5,7 @@ for (i in [1, 2, 3]) {
   list.add(new Fn { IO.print(j) })
 }
 
-for (f in list) f.call
+for (f in list) f.call()
 // expect: 2
 // expect: 3
 // expect: 4

test/for/only_evaluate_sequence_once.wren

@@ -3,7 +3,7 @@ var f = new Fn {
   return [1, 2, 3]
 }
 
-for (i in f.call) IO.print(i)
+for (i in f.call()) IO.print(i)
 // expect: evaluate sequence
 // expect: 1
 // expect: 2

test/for/return_closure.wren

@@ -4,6 +4,6 @@ var f = new Fn {
   }
 }
 
-var g = f.call
-g.call
+var g = f.call()
+g.call()
 // expect: 1

test/for/return_inside.wren

@@ -4,5 +4,5 @@ var f = new Fn {
   }
 }
 
-IO.print(f.call)
+IO.print(f.call())
 // expect: 1

test/function/empty_body.wren

@@ -1,2 +1,2 @@
 var f = new Fn {}
-IO.print(f.call) // expect: null
+IO.print(f.call()) // expect: null

test/function/newline_body.wren

@@ -1,4 +1,4 @@
 var f = new Fn {
   // Hi.
 }
-IO.print(f.call) // expect: null
+IO.print(f.call()) // expect: null

test/function/newline_in_expression_block.wren

@@ -1,5 +1,5 @@
 new Fn { IO.print("ok") // expect error
-}.call // expect error
+}.call() // expect error
 
 // The second error is cascaded here. If it starts failing, just remove that
 // expectation.

test/function/no_parameters.wren

@@ -0,0 +1 @@
+new Fn {|| null } // expect error

test/function/parameters.wren

@@ -1,5 +1,5 @@
 var f0 = new Fn { 0 }
-IO.print(f0.call) // expect: 0
+IO.print(f0.call()) // expect: 0
 
 var f1 = new Fn {|a| a }
 IO.print(f1.call(1)) // expect: 1

test/function/syntax.wren

@@ -1,16 +1,16 @@
 // Single expression body.
-new Fn { IO.print("ok") }.call // expect: ok
+new Fn { IO.print("ok") }.call() // expect: ok
 
 // Curly body.
 new Fn {
   IO.print("ok") // expect: ok
-}.call
+}.call()
 
 // Multiple statements.
 new Fn {
   IO.print("1") // expect: 1
   IO.print("2") // expect: 2
-}.call
+}.call()
 
 // Extra newlines.
 new Fn {
@@ -22,4 +22,4 @@ new Fn {
   IO.print("2") // expect: 2
 
 
-}.call
+}.call()

test/inheritance/inherited_fields_in_closure.wren

@@ -26,11 +26,11 @@ class Bar is Foo {
 }
 
 var bar = new Bar
-IO.print(bar.closeOverFooGet.call.call) // expect: Foo field
-IO.print(bar.closeOverBarGet.call.call) // expect: Bar field
-bar.closeOverFooSet.call.call
-IO.print(bar.closeOverFooGet.call.call) // expect: new foo value
-IO.print(bar.closeOverBarGet.call.call) // expect: Bar field
-bar.closeOverBarSet.call.call
-IO.print(bar.closeOverFooGet.call.call) // expect: new foo value
-IO.print(bar.closeOverBarGet.call.call) // expect: new bar value
+IO.print(bar.closeOverFooGet.call().call()) // expect: Foo field
+IO.print(bar.closeOverBarGet.call().call()) // expect: Bar field
+bar.closeOverFooSet.call().call()
+IO.print(bar.closeOverFooGet.call().call()) // expect: new foo value
+IO.print(bar.closeOverBarGet.call().call()) // expect: Bar field
+bar.closeOverBarSet.call().call()
+IO.print(bar.closeOverFooGet.call().call()) // expect: new foo value
+IO.print(bar.closeOverBarGet.call().call()) // expect: new bar value

test/limit/long_function.wren

@@ -1009,5 +1009,5 @@ new Fn {
   IO.print(9) // expect: 9
   IO.print(10) // expect: 10
   // 1000
-}.call
+}.call()
 

test/limit/many_constants.wren

@@ -65537,4 +65537,4 @@ var f = new Fn {
   IO.print(65536)
 }
 
-f.call // expect: 65536
+f.call() // expect: 65536

test/list/clear.wren

@@ -1,7 +1,7 @@
 var a = [1, 2, 3]
-a.clear
+a.clear()
 IO.print(a)       // expect: []
 IO.print(a.count) // expect: 0
 
 // Returns null.
-IO.print([1, 2].clear) // expect: null
+IO.print([1, 2].clear()) // expect: null

test/map/clear.wren

@@ -1,7 +1,7 @@
 var a = {1: 1, 2: 2, 3: 3}
-a.clear
+a.clear()
 IO.print(a)       // expect: {}
 IO.print(a.count) // expect: 0
 
 // Returns null.
-IO.print({1: 2}.clear) // expect: null
+IO.print({1: 2}.clear()) // expect: null

test/method/arity.wren

@@ -1,5 +1,6 @@
 class Foo {
-  method { 0 }
+  method { "getter" }
+  method() { "no args" }
   method(a) { a }
   method(a, b) { a + b }
   method(a, b, c) { a + b + c }
@@ -19,7 +20,8 @@ class Foo {
 }
 
 var foo = new Foo
-IO.print(foo.method) // expect: 0
+IO.print(foo.method) // expect: getter
+IO.print(foo.method()) // expect: no args
 IO.print(foo.method(1)) // expect: 1
 IO.print(foo.method(1, 2)) // expect: 3
 IO.print(foo.method(1, 2, 3)) // expect: 6

test/method/empty_subscript_call.wren

@@ -0,0 +1,3 @@
+var list = [1, 2]
+list[] // expect error
+"don't actually want error here, but cascades from above" // expect error

test/method/empty_subscript_definition.wren

@@ -0,0 +1,3 @@
+class Foo {
+  [] { "empty" } // expect error
+}

test/nonlocal/assignment.wren

@@ -14,5 +14,5 @@ IO.print(Nonlocal) // expect: method
 
 new Fn {
   Nonlocal = "fn"
-}.call
+}.call()
 IO.print(Nonlocal) // expect: fn

test/nonlocal/use_in_function.wren

@@ -2,4 +2,4 @@ var Global = "global"
 
 new Fn {
   IO.print(Global) // expect: global
-}.call
+}.call()

test/nonlocal/use_in_function_before_definition.wren

@@ -4,4 +4,4 @@ var f = new Fn {
 
 var Global = "global"
 
-f.call // expect: global
+f.call() // expect: global

test/return/after_else.wren

@@ -1,3 +1,3 @@
 IO.print(new Fn {
   if (false) "no" else return "ok"
-}.call) // expect: ok
+}.call()) // expect: ok

test/return/after_if.wren

@@ -1,3 +1,3 @@
 IO.print(new Fn {
   if (true) return "ok"
-}.call) // expect: ok
+}.call()) // expect: ok

test/return/after_while.wren

@@ -1,3 +1,3 @@
 IO.print(new Fn {
   while (true) return "ok"
-}.call) // expect: ok
+}.call()) // expect: ok

test/return/in_function.wren

@@ -3,4 +3,4 @@ var f = new Fn {
   IO.print("bad")
 }
 
-IO.print(f.call) // expect: ok
+IO.print(f.call()) // expect: ok

test/return/return_null_if_newline.wren

@@ -3,4 +3,4 @@ var f = new Fn {
   IO.print("bad")
 }
 
-IO.print(f.call) // expect: null
+IO.print(f.call()) // expect: null

test/static_field/closure.wren

@@ -11,6 +11,6 @@ class Foo {
 }
 
 Foo.initialize
-IO.print(Foo.closeOverGet.call) // expect: Foo field
-Foo.closeOverSet.call
-IO.print(Foo.closeOverGet.call) // expect: new value
+IO.print(Foo.closeOverGet.call()) // expect: Foo field
+Foo.closeOverSet.call()
+IO.print(Foo.closeOverGet.call()) // expect: new value

test/super/closure.wren

@@ -8,4 +8,4 @@ class Derived is Base {
 }
 
 var closure = (new Derived).getClosure
-IO.print(closure.call) // expect: Base
+IO.print(closure.call()) // expect: Base

test/this/closure.wren

@@ -4,4 +4,4 @@ class Foo {
 }
 
 var closure = (new Foo).getClosure
-IO.print(closure.call) // expect: Foo
+IO.print(closure.call()) // expect: Foo

test/this/nested_class.wren

@@ -13,7 +13,7 @@ class Outer {
       }
 
       (new Inner).method
-    }.call
+    }.call()
   }
 
   toString { "Outer" }

test/this/nested_closure.wren

@@ -4,4 +4,4 @@ class Foo {
 }
 
 var closure = (new Foo).getClosure
-IO.print(closure.call.call.call) // expect: Foo
+IO.print(closure.call().call().call()) // expect: Foo

test/variable/undefined_local.wren

@@ -1,3 +1,3 @@
 new Fn {
   IO.print(notDefined)  // expect error
-}.call
+}.call()

test/while/closure_in_body.wren

@@ -7,7 +7,7 @@ while (i < 4) {
   i = i + 1
 }
 
-for (f in list) f.call
+for (f in list) f.call()
 // expect: 2
 // expect: 3
 // expect: 4

test/while/return_closure.wren

@@ -5,6 +5,6 @@ var f = new Fn {
   }
 }
 
-var g = f.call
-g.call
+var g = f.call()
+g.call()
 // expect: i

test/while/return_inside.wren

@@ -5,5 +5,5 @@ var f = new Fn {
   }
 }
 
-IO.print(f.call)
+IO.print(f.call())
 // expect: i