Say it like this
Real examples
"This function modifies the global cache as a side effect, which makes it harder to unit test."
"We discovered that the authentication function had an unexpected side effect of clearing user sessions."
"To improve maintainability, we should refactor these components to minimize side effects."
Don't say this
Handle with care. Non-tech speakers may confuse it with the medical meaning (adverse reaction to medicine). In tech, it refers to when code changes something beyond its intended output, not about negative consequences.
Other forms
side effect
"The function has a side effect that modifies the database."
side effects (plural)
"We need to eliminate the side effects in this module."
side-effect-free or pure
"Pure functions are side-effect-free and easier to test."
Often used with
Similar words
Opposites
Practice
Try it
4 quick exercises
1. Your teammate wrote a function that modifies global variables. You want to flag this in code review. Which sounds most natural?
2. We should refactor the API handler to _______ _______ because it makes testing difficult.
3. Which sentence uses side effect incorrectly?
4. Rewrite this in natural tech English using side effect: The problem with this code is that it changes things it should not change, and that makes it difficult to understand what it does.
Questions
Quick poll
Have you said "side effect" in a standup this week?
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