Changed Tap implementation to fix possible deadlocks. Adjusted for_wi…

…th_range_and_if test to use errors.Lift. Changed errors_lift test to not print out a number anymore. Adjusted examples and other tests for new println implementation.

e2e/cli/build_windows/neva.yml

@@ -1 +1 @@
-neva: 0.31.0
+neva: 0.31.2

e2e/cli/new_and_run/neva.yml

@@ -1 +1 @@
-neva: 0.31.0
+neva: 0.31.2

e2e/compiler_error_unused_outport/main/main.neva

@@ -3,17 +3,17 @@ import { fmt }
 def Main(start any) (stop any) {
     sub1 SubComponent
     sub2 SubComponent
-    panic Panic
     ---
     :start -> 'Hi, Neva!' -> sub1:data
     sub1:stop-> :stop
     '1' -> sub2
-    [sub1:err, sub2:err] -> panic
 }
 
-def SubComponent(data string) (stop any, err error) {
-    println fmt.Println?
+def SubComponent(data string) (stop any) {
+    println fmt.Println
+    panic Panic
     ---
     :data -> println:data
     println:res -> :stop
+    println:err -> panic
 }

e2e/errors_lift/e2e_test.go

@@ -14,7 +14,7 @@ func Test(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(
 		t,
-		"42\n",
+		"",
 		string(out),
 	)
 

e2e/errors_lift/main/main.neva

@@ -15,7 +15,5 @@ def Main(start any) (stop any) {
 
 // Handler doesn't have error outport.
 def Handler(data any) (res any) {
-    println fmt.Println<any>
-    ---
-    :data -> '42' -> println -> :res
+    :data -> :res
 }

e2e/errors_must/main/main.neva

@@ -8,8 +8,11 @@ import {
 def Main(start any) (stop any) {
     println fmt.Println<any>
     must_handle errors.Must<any, any>{Handler}
+    panic Panic
     ---
-    :start -> 'create_me.txt' -> must_handle -> 'success!' -> println -> :stop
+    :start -> 'create_me.txt' -> must_handle -> 'success!' -> println
+    println:res -> :stop
+    println:err -> panic
 }
 
 // Handler have error outport.
@@ -18,5 +21,5 @@ def Handler(data string) (res any, err error) {
     ---
     :data -> write_all:filename
     'Hello, io.WriteAll!' -> write_all:data
-    write_all -> :res
+    write_all:res -> :res
 }

e2e/for_with_range_and_if/e2e_test.go

@@ -8,7 +8,6 @@ import (
 )
 
 func Test(t *testing.T) {
-	t.Skip("Remove this skip, until errors.Lift has been implemented.")
 	for i := 0; i < 10; i++ {
 		t.Run("", func(t *testing.T) {
 			cmd := exec.Command("neva", "run", "main")

e2e/for_with_range_and_if/main/main.neva

@@ -10,11 +10,13 @@ def Main(start any) (stop any) {
 	for:err -> panic
 }
 
-def PrintAsNum(data bool) (sig any) {
+def PrintAsNum(data bool) (res any, err error) {
 	Ternary, fmt.Println
 	---
 	:data -> ternary:if
 	1 -> ternary:then
 	0 -> ternary:else
-	ternary -> println -> :sig
+	ternary -> println
+	println:res -> :res
+	println:err -> :err
 }

e2e/slow_iteration_with_for/main/main.neva

@@ -14,12 +14,12 @@ def Main(start any) (stop any) {
     for:err -> panic
 }
 
-def Slow(data int) (sig any, err error) {
+def Slow(data int) (res any, err error) {
     time.Delay<int>
     fmt.Println<int>?
     ---
     :data -> delay:data
     $time.second -> delay:dur
     delay -> println:data
-    println:res -> :sig
+    println:res -> :res
 }

examples/99_bottles/main.neva

@@ -10,15 +10,16 @@ def Main(start any) (stop any) {
 	print:err -> panic
 }
 
-def Next2Lines(data int) (sig any, err error) {
+def Next2Lines(data int) (res any, err error) {
 	first Tap<int>{FirstLine}?
 	dec Dec<int>
 	second SecondLine?
 	---
-	:data -> first -> dec -> second -> :sig
+	:data -> first
+	first:res -> dec -> second -> :res
 }
 
-def FirstLine(data int) (sig any, err error) {
+def FirstLine(data int) (res any, err error) {
 	p1 fmt.Println?
 	p2 fmt.Println?
 	p3 fmt.Printf?
@@ -31,10 +32,10 @@ def FirstLine(data int) (sig any, err error) {
 			'$0 bottles of beer on the wall, $0 bottles of beer.\n' -> p3:tpl
 		]
 	}
-	[p1:res, p2:res, p3:sig] -> :sig
+	[p1:res, p2:res, p3:sig] -> :res
 }
 
-def SecondLine(data int) (sig any, err error) {
+def SecondLine(data int) (res any, err error) {
 	p1 fmt.Println?
 	p2 fmt.Println?
 	p3 fmt.Println?
@@ -49,5 +50,5 @@ def SecondLine(data int) (sig any, err error) {
 			'Take one down and pass it around, $0 bottles of beer on the wall.\n\n' -> p4:tpl
 		]
 	}
-	[p1:res, p2:res, p3:res, p4:sig] -> :sig
+	[p1:res, p2:res, p3:res, p4:sig] -> :res
 }

examples/file_write_all/main.neva

@@ -1,12 +1,13 @@
 import { io, fmt }
 
 def Main(start any) (stop any) {
-	io.WriteAll, fmt.Println
+	io.WriteAll, fmt.Println, Panic
 	---
 	:start -> [
 		'file_writer_example.txt' -> writeAll:filename,
 		'Hello, io.WriteAll!' -> writeAll:data
 	]
 	writeAll:err -> println
-	[writeAll:res, println] -> :stop
+	[writeAll:res, println:res] -> :stop
+	println:err -> panic
 }

examples/image_png/main.neva

@@ -32,6 +32,7 @@ def Main(start any) (stop any) {
 	image.New, image.Encode
 	NewPixel, NewColor, NewStream,
 	io.WriteAll, printErr fmt.Println
+	panic Panic
 	---
 	:start -> [
 		0 -> [newColor:r, newColor:g, newColor:b, newColor:a],
@@ -44,5 +45,6 @@ def Main(start any) (stop any) {
 	new:img -> encode:img
 	encode:data -> writeAll:data
 	[new:err, encode:err, writeAll:err] -> printErr
-	[writeAll:res, printErr] -> :stop
+	[writeAll:res, printErr:res] -> :stop
+	printErr:err -> panic
 }

std/builtin/core.neva

@@ -64,13 +64,19 @@ pub def Pass<T>(data T) (res T) {
 // sends a signal when finishes. Signal could be of any type, so no need for
 // dealing with locks manually. Handler can send error, in that case `Tap` will
 // propagate it up to parent node.
-pub def Tap<T>(data T) (res T) {
+pub def Tap<T>(data T) (res T, err error) {
+    proxy1 Pass<T>
+    proxy2 Pass<T>
     lock Lock<T>
     handler ITapHandler<T>
     ---
-    :data -> [handler, lock:data]
-    handler -> lock:sig
+    :data -> [lock:data, handler]
+
+    handler:res -> proxy1
+    handler:err -> [proxy2, :err]
+
+    [proxy1, proxy2] -> lock:sig
     lock -> :res
 }
 
-pub interface ITapHandler<T>(T) (any)
+pub interface ITapHandler<T>(T) (res any, err error)