Re: [Jprogramming] Tacit argument checking

[Kip Murray]

So you can.  That's better.

Sherlock, Ric wrote:

From: Kip Murray

I found system verb assert in ~system\main\stdlib.ijs and learned how to
use it from Roger's The
Ball Clock Problem below.  Here is my final exam paper:

    NB. From ~system\main\stdlib.ijs
    NB. =========================================================
    NB.*assert v assert value is true
    NB. assertion failure if  0 e. y
    NB. e.g. 'invalid age' assert 0 <: age
    assert=: 0 0"_ $ 13!:8^:((0: e. ])`(12"_))

    string =: 'domain error: arguments must be >0 and not _ '

    f =: (^. [ string"_ assert 0&< *. _&>)"0 :[:

    NB. Because of [ the result is ^. y provided the assert succeeds

    f 1 2 3
0 0.693147 1.09861

Can use NVV fork:

f2 =: (^. [ string assert 0&< *. _&>)"0 :[:
   f2 1 2 3
0 0.693147 1.09861

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