repl: functions and conditional blocks support

compiler/tests/repl/conditional_blocks.repl

@@ -0,0 +1,18 @@
+if true {
+  println('foo')
+}
+for i := 0; i < 4; i++ {
+  println(i)
+}
+if false {
+  println('foo')
+} else {
+  println('bar')
+}
+===output===
+foo
+0
+1
+2
+3
+bar

compiler/tests/repl/function.repl

@@ -0,0 +1,11 @@
+fn test() {
+  println('foo')
+}
+test()
+fn test2(a int) {
+  println(a)
+}
+test2(42)
+===output===
+foo
+42

compiler/tests/repl/repl_test.v

@@ -14,7 +14,7 @@ fn test_repl() {
       assert false
       break
     }
-    result := r.output.replace('>>> ', '').replace('>>>', '').all_after('Use Ctrl-C or `exit` to exit\n')
+    result := r.output.replace('>>> ', '').replace('>>>', '').replace('... ', '').all_after('Use Ctrl-C or `exit` to exit\n')
     assert result == output
     if result != output {
       println(file)