Re: Nitpicking the code (Was: Experiences with match() subexpressions?)

On 14.04.2025 20:20, Kenny McCormack wrote:

In article <vtgtkr$3br8e$1@dont-email.me>,
Ed Morton  <mortonspam@gmail.com> wrote:
...

    data = "R=\"R=r1,R=r2\",R=r2,R=r3,E=e"
    nf = patsplit(data, arr, /[RE]=([^,]*|"([^"]|"")*")/)
    delete arr
    for ( i in arr ) {
        sub(/[^=]+=/, "", arr[i])
    }

 
This can't be right, since if the sequence:
    delete arr
    for (i in arr) ...
can't possibly do anything.  I.e., the for statement will be a no-op, since
the array is empty at that point.
 

or any awk:
>
    data = "R=\"R=r1,R=r2\",R=r2,R=r3,E=e"
    nf = 0
    delete arr
    while ( match(data, /[RE]=([^,]*|"([^"]|"")*")/, a) ) {
        arr[++nf] = substr(data, RSTART+2, RLENGTH-2)
        data = substr(data, RSTART+RLENGTH)
    }

 
I believe "delete arr" (without an index, hence removing the entire array)
is an "extension".  I can't quite quote chapter and verse, but I note that
"man mawk" explicitly mentions that mawk supports this syntax, thereby
implying that it isn't "standard".  Of course, gawk supports it as well.
 
So, if by "any awk", you mean "strictly standard", then, well, you can see
where I am going with this.

I seem to recall that a standard way to clear an array could be using
  split("", arr)
for example. To my taste it looks a bit clumsy, not as nice as using
'delete', but well, whatever one prefers.

Janis