Re: [bug-gawk] Gawk Enhancement Suggestion

[Ed Morton]

Arnold - I'll take a look and get back to you. I expect I can code up what I 
have in mind (which isn't quite what's in that example) as an awk function that 
people could copy/paste but I was really hoping to get a new builtin string 
function out of this.

Thanks,

    Ed.

On 12/6/2011 2:38 PM, Aharon Robbins wrote:
> Hi Ed.
>
> Re the below. See the node "Cut Program" in the gawk manual.
> Adaptation into a function should be straightforward.
>
> A diff to redo that section as a function + code to call it will
> be cheerily reviewed and most likely accepted.
>
> Thanks,
>
> Arnold
>
> > Date: Fri, 02 Dec 2011 07:36:50 -0600
> > From: Ed Morton<address@hidden>
> > To: address@hidden
> > Subject: [bug-gawk] Gawk Enhancement Suggestion
> >
> > Arnold - could we get a "cut()" function for gawk similar to the UNIX
> > one of the same name that just lets people select specific fields or
> > ranges of fields?  Below is some details (copied from something I posted
> > at comp.lang.awk).
> >
> > Regards,
> >
> >       Ed.
> >
> > A function that returns a string of selected fields is very often all we need. 
> > e.g.:
> >
> > print cut($0,3)       # print from the 3rd field to the end of the record using
> > FS as separator
> > print cut($0,3,",")   # print from the 3rd field to the end of the record using
> > "," as separator
> > print cut($0,"3-7")   # print from the 3rd field to the 7th field
> > print cut($0,"3,5,7") # print the 3rd, 5th, and 7th fields
> >
> > The separating substring between the fields would just be whatever separator
> > preceeded the trailing fields. So, with this input (with leading blanks):
> >
> >       a b    c  d
> >
> > the following code snippets would produce the output that follows them:
> >
> > print cut($0,"1,3")
> > a    c
> >
> > print cut($0,"1,3",/[[:blank:]]+/)
> >    b
> >
> > print cut($0,"1-3")
> > a b    c
> >
> > print cut($0,"2,4")
> > b  d
> >
> > print cut($0,"1-4")
> > a b    c  d
> >
> > Obviously $0 can be replaced by any string and cut() should take an optional 4th
> > arg to specify the separator in it's returned string:
> >
> > print cut($0,"1,3",FS,OFS)
> > a c
> >
> > print cut($0,"1,3",/[[:blank:]]+/,"#")
> > #b
> >
> > print cut($0,"1-3",FS,OFS)
> > a b c
> >
> > print cut($0,"2,4",FS,":")
> > b:d
> >
> > print cut($0,"1-4",FS,"|")
> > a|b|c|d