Lesson 14 of 55
8 mins readC-Style Three-Part for Loops
In Plain English
Perl supports traditional C-style `for (init; test; step)` loops for numeric iteration and matrix scanning.
Deep Dive: How It Works
Three Expressions: `for (my $i = 0; $i < $limit; $i++)`.
Lexical Iterator: Declaring `my $i` restricts the index variable to the loop block.
Step Variations: Step by any increment (e.g., `$i += 2`, `$i *= 10`).
Core Rules to Remember
C-Style Loops: Ideal when exact numeric indices or custom step sizes are required.
Lexical Loop Variables: Always declare `my $i` in the loop header to prevent variable leakage.
Live Interactive Example
Hit Run Code to see it liveCounting Even Numbers
Python 3.12
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Output Console
Click "Run Code" to view the rendered output.
How it works: $i started at 2, increased by 2 each step, and stopped after 8.
Your Turn: Micro Challenge
No pressure! Edit the starter code below and test your solution with instant feedback.
Micro Exercise
Print Multiples of 5
- Use a `for` loop to print multiples of 5 from 5 up to 20 separated by spaces.
- Print `"\n"` after the loop.
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Sandbox Output
Click "Run & Check" to test your solution.
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