Search Result for "hidden flag":
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2 definitions retrieved:

The Jargon File (version 4.4.7, 29 Dec 2003):

hidden flag n. [scientific computation] An extra option added to a routine without changing the calling sequence. For example, instead of adding an explicit input variable to instruct a routine to give extra diagnostic output, the programmer might just add a test for some otherwise meaningless feature of the existing inputs, such as a negative mass. The use of hidden flags can make a program very hard to debug and understand, but is all too common wherever programs are hacked on in a hurry.
The Free On-line Dictionary of Computing (18 March 2015):

hidden flag (scientific computation) An extra option added to a routine without changing the calling sequence. For example, instead of adding an explicit input variable to instruct a routine to give extra diagnostic output, the programmer might just add a test for some otherwise meaningless feature of the existing inputs, such as a negative mass. The use of hidden flags can make a program very hard to debug and understand, but is all too common wherever programs are hacked in a hurry. [Jargon File] (1994-11-24)