From 3d0be3647a4560b4e461dbdfca09de7536e04f57 Mon Sep 17 00:00:00 2001
From: Charles Cabergs <me@cacharle.xyz>
Date: Tue, 24 Nov 2020 14:35:41 +0100
Subject: Added python's list comprehension draft

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 blog/python_list_comprehension.md | 87 +++++++++++++++++++++++++++++++++++++++
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+# Python's list comprehension
+
+List comprehension are the best feature of Python. They allow us to map and filter the elements of lists.
+
+## Mapping
+
+You can change each element of a list.
+
+```
+>>> xs = [x * x for x in range(10)]
+>>> xs
+[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
+>>> [x + 10 for x in xs]
+[10, 11, 14, 19, 26, 35, 46, 59, 74, 91]
+```
+
+### Syntax
+
+```
+[<expr> for <element> in <iterable>]
+```
+
+The result of `<expr>` will be the value of the element.
+
+### Comparison
+
+```
+result = []
+for <element> in <iterable>:
+    result.append(<expr>)
+```
+
+## Filter
+
+You can filter out elements.
+
+```
+>>> [x for x in range(10) if x % 2 == 0]
+[0, 2, 4, 6, 8]
+>>> [x * x for x in range(10) if x > 5]
+[36, 49, 64, 81]
+```
+
+### Syntax
+
+```
+[<expr> for <element> in <iterable> if <condition>]
+```
+
+The result of `<expr>` will be the value of the element if `<condition>` is `True`.
+
+### Comparison
+
+```
+result = []
+for <element> in <iterable>:
+    if <condition>:
+        result.append(<expr>)
+```
+
+## Other comprehension
+
+### Dictionnary
+
+```
+>>> {k: v * v for k, v in {"foo": 1, "bar": 2}.items()}
+{"foo": 1, "bar": 4}
+```
+
+### Set
+
+```
+>>> {x for x in [1, 2, 3, 1, 1, 1, 2, 1]}
+{1, 2, 3}
+```
+
+### Generator
+
+```
+>>> gen = (x * x for x in range(10))
+>>> next(gen)
+0
+>>> next(gen)
+1
+>>> next(gen)
+4
+```
-- 
cgit