Re: [bug-gawk] FPAT bug?

[Ed Morton]

FWIW it looks like users can work around it for now by re-setting FPAT for every 
record:

$ cat tstFPAT.awk
BEGIN { FPAT="[^,]*" }
{
    oFPAT=FPAT; FPAT=""; FPAT=oFPAT

    print NF, $0
    for (i=1;i<=NF;i++)
        print 1, "\t" i, "[" $i "]"
    print ""
}

$ awk -f tstFPAT.awk file1.csv
3 ,,3
1       1 []
1       2 []
1       3 [3]

3 ,,3
1       1 []
1       2 []
1       3 [3]

Might be useful until a fix is available. Any better ideas for now?

Regards,

     Ed.

On 4/1/2017 12:08 PM, Andrew J. Schorr wrote:
> On Sat, Apr 01, 2017 at 10:28:47AM -0500, Ed Morton wrote:
> > OK, thanks for the update!
> Just to confirm that this is a bug: I think the results must be
> consistent with the patsplit function. In 4.1.4, it says:
>
> bash-4.2$ ./gawk 'BEGIN {nf = patsplit(",,3", f, "[^,]*"); for (i = 1; i <= nf; i++) 
> printf "%d [%s]\n", i, f[i]}'
> 1 []
> 2 []
> 3 [3]
>
> That is clearly inconsistent with:
>
> bash-4.2$ (echo ,,3; echo ,,3) | ./gawk -v "FPAT=[^,]*" '{for (i = 1; i <= NF; i++) 
> printf "%d [%s]\n", i, $i}'
> 1 []
> 2 []
> 3 [3]
> 1 []
> 2 [3]
>
> So 4.1.4 is internally inconsistent; the first record was parsed correctly, but
> the second was not.  The only remaining question is how to fix this properly...
>
> Regards,
> Andy