62 lines
2 KiB
Markdown
62 lines
2 KiB
Markdown
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---
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title: >
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Don't use "else"
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pubDate: 2023-09-11
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permalink: >-
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archive/2023/09/11/dont-use-else
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tags:
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- software-development
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- clean-code
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---
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A popular approach to writing clean code is to avoid the "else" keyword and, if possible, avoid nesting `if` statements within other `if` statements.
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If I look at some code, I want to see as few indentation levels as possible, making the code easier to read and understand.
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## What should I do instead?
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Instead, you check for a condition; if that isn't met, you return early.
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For example, here is some code I saw recently during a meetup talk:
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```php
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$callingClass = $scope->getClassReflection()->getName();
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if ($callingClass === TextMessageQueueProcessor::class) {
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return [];
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}
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$type = $scope->getType($node->var);
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foreach ($type->getReferencedClasses() as $targetClass) {
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if ($targetClass === TextMessageSender::class) {
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return [
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RuleErrorBuilder::message(
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sprintf(
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"Can not call %s from %s",
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$targetClass,
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$callingClass
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)
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)->build()
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];
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}
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}
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return [];
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```
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There are no `else` statements.
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If the calling class isn't of the required type, it returns immediately with no violations, and we continue, knowing the calling class must be what we need.
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If the target class is one where the code shouldn't be called from, it returns immediately with the violation.
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Finally, if no violations were found within the referenced classes, it returns an empty array.
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## Here's the thing
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The code always returns an array of rule violations but does so as soon as possible at each point.
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The code is clean and readable, and I can understand it, knowing once each condition is passed, I don't need to continue thinking about it.
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Whilst there are some situations to use `else`, most of the time I've found that I can use an early return instead.
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