New(ish) option on the filter command

[Alex Tweedly]

On 16/07/2016 00:22, [-hh] wrote:

> Usually one would do
> put cr & resultOfFilter2 after resultOfFilter1
Well, that depends ... if the first one had produced no matches, then 
this statement would introduce a spurious blank line.
> So the problem could be:
>
> What should "filter .. after tVar" exactly do?
It should simply concatenate. Just like
   put myVar after myOtherVar
does.

If I had done it the old-fashioned way, like
    filter t with "*.jpg" into t1
    filter t with "*.jpeg" into t2
    put t1 & CR & t2 into myFinalVar
then I would have needed to know that files(), and filter, both omit the 
final CR, and deal with it accordingly.
So there's no reason for "filter ... after myVar" to try to be any 
cleverer than "put ... after myVar"


> Simply concatenate?
> Or use the current linedelimiter as "connector"?
-- Alex.
P.S. I could, of course, revive my old rant about the need for *proper* 
lists in LC Script, rather than always mimicking them as lines where we 
need to deal with trailing, or intermediate, delimiters, etc. Then we 
could avoid complexities like
function concatenateLines p1, p2
   put p1 into tResult
   if p1 is not empty AND p2 is not empty AND the last char of p1 <> CR 
then put CR after tResult
   put p2 after tResult
   return tResult
end concatenateLines
>
> Alex Tweedly wrote
>> OK, so it's not that new - it was added in 6.1 :-)
>>
>> filter now allows you to specify a "target container", e.g.
>>
>>     filter myVar with "*.livecode"  into tStacks
>>
>>
>> Would it be a reasonable enhancement request to allow not just "into",
>> but also "after" and "before" ?
>>
>> e.g.
>>
>>    put files() into t
>>
>>    filter t with "*.jpg" into tFiles
>>
>>    filter t with "*.jpeg" after tFiles
>>
>> etc.
>>
>> btw - if you are hopeful and just try the "after variant", it doesn't
>> give you an error - it simply ignores the "after targetContainer" part,
>> and filters the source container. Seems to me that's a bug - anyone
>> agree and I'll enter it as such ?
>>
>> -- Alex.
>>
>>
>>
>>
>>
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>
>
>
>
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