fall through meaning: definition, etymology and quotations

fall through

verbalso spelled fall-through

Used other than figuratively or idiomatically: see fall, through.

Idiomatic To be unsuccessful, come to nothing; to be cancelled; not to proceed.

Their plans to go hiking Saturday fell through because it rained.
Lynton & Barnstaple Railway revivalists have unexpectedly been given a second chance to purchase the station, after the original sale deal fell through.2020 July 1, Howard Johnston, “Regional News: Western: Bratton Fleming”, in Rail, page 24:

Derived terms: fallthrough, fall-through

fall-through

noun

Etymology Deverbal from fall through.

Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Programming, Sciences In certain programming constructs, the situation where execution passes to the next condition in a list unless explicitly redirected.

It is a good idea to comment the (rare) cases in which a fall-through is intentional so that an uncommented fall-through can be assumed to be an error.1997, Bjarne Stroustrup, The C++ Programming Language: Language Libraries and Design:
If you place default elsewhere, then a break will be required to prevent fall-through.2001, Graham M Seed, Barry J Cooper, An Introduction to Object-Oriented Programming in C++:

1 more example

Specifically, it prohibits fall-through conditions in almost all cases.2008, Nagel et al, Professional C# 2008

Related terms: flowthrough, passthrough