Merge pull request #13 from fink-lang/fix-insert_at

fix(iter): fix insert_at to insert into empty iterable or at end

Author: kollhof

src/iter.fnk

@@ -30,15 +30,24 @@ chain = fn ...iterables:
       ...iterable
 
 
+
 insert_at = fn idx, insert_items: fn items:
+  ignore = {}
+
   pipe items:
+    chain ?, [ignore]
+
     map item, curr=0:
       all = match curr:
         idx: chain insert_items, [item]
         else: [item]
 
       (...all, curr + 1)
 
+    filter item:
+      item != ignore
+
+
 
 cycle = fn iterable:
   pipe [...iterable]:

src/iter.test.fnk

@@ -76,6 +76,20 @@ describe 'iter - transforming funcs', fn:
       to_equal
         '123abc456'
 
+    expect
+      pipe '1':
+        insert_at 0, 'abc'
+        join ''
+      to_equal
+        'abc1'
+
+    expect
+      pipe '1':
+        insert_at 1, 'abc'
+        join ''
+      to_equal
+        '1abc'
+
 
   it 'creates unique set of items', fn:
     expect