dseeni / looper

For loop macros for Nim

Looper — for loop macros for Nim

About

This nimble package contains for loop macros. This is an expiremental Nim future. They work like inline iterators - only called from for loops.

The zip macro

import looper
let
   a = [1, 3, 5, 7]
   b = @[0, 2, 4, 6, 8]
   c = @["one", "two", "three", "four", "five"]

# It supports variadic arguments of different types,
# each container type must support indexing

for (x, y, z) in zip(a, b, c):
   echo x, " ", y, " ", z

# Also written as:
for x, y, z in zip(a, b, c):
   echo x, " ", y, " ", z

# This is supported too:
for w in zip(a, b, c):
   echo w

The enumerate macro

import looper
let
   a = [1, 3, 5, 7]

for (i, x) in enumerate(a.iter):
   echo i, " ", x

# Also written as:
for i, x in enumerate(a.iter):
   echo i, " ", x

Known quirks

• Nested tuple unpacking for (i, (x, y)) in enumerate(iterable) is invalid syntax you have to write for i, (x, y) in enumerate(iterable) instead.

• The enumerate macros doesn't support tuples: for w in enumerate(iterable) this is because of the way it is implemented.

License

This library is distributed under the MIT license. For more information see copying.txt.