thenblock

In programming, a thenblock is a block of code associated with a then clause in languages that use explicit then-branches or with asynchronous APIs that chain operations. The term is informal and not universally standardized, but it is commonly used to describe the contiguous statements that execute after a condition evaluates to true or after a previous operation completes.

In conditional constructs, the thenblock follows the condition and is executed when the condition holds. It is typically delimited by an end marker or by indentation, and it may contain statements, declarations, or nested blocks. For example, in languages with an explicit then branch, a structure like if condition then followed by the thenblock and eventually closed with an end marker would execute the thenblock when condition is true.

In asynchronous programming, a thenblock refers to the function or block supplied to a then method on a promise or future. This block runs when the promise resolves, and it is commonly used to process results, chain subsequent operations, or handle errors via retry logic or dedicated error handlers.

Although the exact syntax varies across languages, the concept of a thenblock remains a core part of readability and control flow, marking the set of statements that should run once the prerequisite condition or operation has completed.