Lesson 18 of 55
7 mins readPython Postfix Loops (Modifier Loops)
In Plain English
Similar to postfix conditionals, `EXPRESSION for LIST;` executes an expression once for each element of the list, binding `$_` to each item.
Deep Dive: How It Works
Postfix Loop Syntax: `print "$_\n" for @items;`.
Topic Binding: Automatically binds `$_` as the loop iterator.
Conciseness: Replaces multi-line blocks with crisp single-line idioms.
Core Rules to Remember
Postfix for: Runs the expression once per element in the list.
Compact Idiom: Extensively used in Perl scripts for transformation and logging.
Live Interactive Example
Hit Run Code to see it livePostfix Iteration Examples
Python 3.12
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Output Console
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How it works: The postfix loop executed the statement for every element.
Your Turn: Micro Challenge
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Micro Exercise
Print Server Nodes with Postfix for
- Declare `my @nodes = ("node-1", "node-2", "node-3");`
- Print `"Active: $_\n"` for each node using a postfix `for @nodes;`.
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Sandbox Output
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