Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Flip-flop (programming)
open-in-new
<p>In <a href="/facts/Computer_programming/QmSsFnu0">computer programming</a>, a flip-flop is a seldom-used syntactic construct which allows a boolean to flip from false to true when a first condition is met and then back to false when a second condition is met. The syntax is available in the programming languages <a href="/facts/Perl/fx31kjlT">Perl</a> and <a href="/facts/Ruby_/BeYSaPSR">Ruby</a>. Similar logic is available in <a href="/facts/Sed/5pXUwRdD">sed</a> and <a href="/facts/Awk/lAQ0leyj">awk</a>. </p><p>A flip-flop with first condition A and second condition B is not equivalent to "if A and not B", as the former has persistent state and is true even if A is no longer true, as long as at some point in the past A was true and B has always been false. </p><p>A good analogy would be that even though A is not the truth and B is, It still will believe A. </p>