[Jprogramming] Feedback on beginner's code

[Henry Rich]

> Again, smaller sub-units help to avoid such accidents:
>
> 	sort =: /:~
> 	de_space =: -.&' '
> 	normalize =: de_space at sort@tolower
> 	isAnagramOf =: -:&normalize
>
> Almost every time, these tiny sub-units provide something useful even
> beyond of the current context ("anagrams").  They are certainly easier
> to test/verify.

Emphatically agreed.  And also take a moment to decide the proper rank for a verb.  Here,
isAnagramOf applies only to lists, so define it as

isAnagramOf =: -:&:normalize"1   NB. & would be OK too

de_space might reasonably be rank 1 as well.

>
> It also makes reasoning about the ranks of the components easier.
> In consequence, it becomes easier to make an educated selection
> between  @ vs @:  or & vs &:  -- much better than to stick blindly
> to some mysterious rule of thumb.

I would rather say that the goal is to understand why the rule of thumb is not mysterious.
The first step is to note that there is a difference between & and &:, @ and @:,
and &. and &.: - something many J newcomers pick up late.

Henry Rich

>
> 							Martin Neitzel
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