Merge branch 'list-forall' of git://github.com/gsmaverick/wren into gsmaverick-list-forall

builtin/core.wren

@@ -14,6 +14,13 @@ class Sequence {
     }
     return result
   }
+
+  all(f) {
+    for (element in this) {
+      if (!f.call(element)) return false
+    }
+    return true
+  }
 }
 
 class List is Sequence {

doc/site/core-library.markdown

@@ -313,6 +313,10 @@ Removes all items from the list.
 
 The number of items in the list.
 
+### **forall(predicate)**
+
+Tests whether all the elements in the list pass the `predicate`.
+
 ### **insert**(item, index)
 
 **TODO**

src/wren_core.c

@@ -57,6 +57,13 @@ static const char* libSource =
 "    }\n"
 "    return result\n"
 "  }\n"
+"\n"
+"  all(f) {\n"
+"    for (element in this) {\n"
+"      if (!f.call(element)) return false\n"
+"    }\n"
+"    return true\n"
+"  }\n"
 "}\n"
 "\n"
 "class List is Sequence {\n"

test/list/forall.wren

@@ -0,0 +1,9 @@
+var a = [1, 2, 3]
+var b = a.all {|x| x > 1 }
+IO.print(b) // expect: false
+
+var d = a.all {|x| x > 0 }
+IO.print(d) // expect: true
+
+var e = [].all {|x| false }
+IO.print(e) // expect: true

test/list/forall_non_bool_returning_fn.wren

@@ -0,0 +1 @@
+[1, 2, 3].all {|x| "string" } // expect runtime error: String does not implement method '!' with 0 arguments.

test/list/forall_non_function_arg.wren

@@ -0,0 +1 @@
+[1, 2, 3].all("string") // expect runtime error: String does not implement method 'call' with 1 argument.