Discussion on: Python Map Function

[Giora Guttsait]

Very cute! The first example also made me realise that map, filter, and the likes, that work on iterables, are lazy.

def newfunc(val):
  print('lazy ' + str(val)) # this is proof for lazy
  return val * 2

result = map(newfunc, [1, 2, 3, 4]) 
print(result) # prints the map object, but the newfunc operation
              # was not invoked on any of the values
print(next(result)) # only invokes newfunc on 1
print(list(result)) # invokes newfunc on the rest

repl.it example

[Python Geeks]

Awesome! It's an interesting thing that I haven't known yet. Thanks a lot for your sharing.
Btw, Don't you mind if I share your example in the original post? It will help other developers more understand map and filter.

[Giora Guttsait]

Also, notice that my code example has syntax highlighting.

This is because I use

```python
def some_method():
    pass
```

Instead of

```
def some_method():
    pass
```

[Python Geeks]

Thanks for the notice. It helps me a lot. :)

[Giora Guttsait]

I most certainly don't mind :)