FileMaker If Evaluation

Monday 31st March, 2014

An interesting question came up at work this week. Does FileMaker use lazy evaluation for its control structure conditions or not?

In other words, does TEST get evaluated in the following statement?

If( False and TEST ; 1 ; 0 )

The quick way to settle the question was to use a global variable assignment - i.e. make TEST set a global variable using a Let.

If( False and Let( $$test = "Eager!" ; True ) ; 1 ; 0 )

Evaluate this in the the Data Viewer, and you shouldn’t see the global variable $$test appearing. For the doubting Thomasinas out there,

If( True and Let( $$test2 = "Test Completed!" ; True ) ; 1 ; 0 )

can also be evaluated, to prove that $test would have been evaluated if the first condition had been True rather than False. QED.