ENGLISH
REFERENCE

handler

n. countable
C1 Advanced US //ˈhændəɫɝ// UK //hˈændlɐ// han·dler

n. a piece of code that waits for a specific event to happen and then reacts to it. For example, you might have one that runs when a user clicks a button.

n. a routine or function that is executed in response to a specific event or signal. Often used in asynchronous programming to manage user inputs or system interrupts.


SIMPLE

The click handler runs when you press the button.

CONTEXTUAL

The developer wrote a custom error handler to catch and log any issues during the data upload process.

COMPLEX

By decoupling the event handler from the main logic, the application remains responsive even when processing high volumes of incoming network requests.

Synonyms
Usage

Often appears in compound nouns like 'event handler', 'error handler', or 'interrupt handler'.

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