6 ms·

awk is a full programming language, and most of the times that I'm doing awk scripting I have to use things like associative arrays and arithmetic. Pulling out

• burntsushi 9y ago
  Yeah, ripgrep is "a grep," not an awk. I'm not sure how they wound up being conflated here. ripgrep does have a `-r/--replace` flag which is somewhat of a generalization of grep's `-o/--only-matching` flag (and also part of ack, I believe) by permitting sub-capture expansion that probably does replace awk for the "pulling out a field from a line" use case you mentioned. But it's pretty awkward for simple cases. e.g., I'd much rather use `blah | awk '{print $2}'` to get the second field delimited by arbitrary whitespace.
  • coldtea 9y ago
    >Yeah, ripgrep is "a grep," not an awk. I'm not sure how they wound up being conflated here. Simple: a lot of people use awk just as a grep.
• fiddlerwoaroof 9y ago
  The main reason I use awk 90% of the time is that its field parsing algorithm does "the right thing" in most cases (i.e. divide fields by 1 or more whitespace characters) without a lot of boilerplate, so it's really easy to throw into a pipeline.
  • cyphar 9y ago
    That's what I was referencing when I said > Pulling out a field from a line is what most people use awk for, but it's honestly the least interesting part of awk. In fact, if cut supported regular expressions for specifying the field and record separators people wouldn't be using awk for that purpose (because that's all that $n does). There's nothing magical about awk's default FS. It's literally just /\s+/. If cut's -d was slightly more clever you wouldn't need to use awk.
    • bewuethr 9y ago
      The default FS throws away leading blanks, though, which doesn't happen if you set it explicitly to \s+, so a tiny little bit of magic does go on after all.
      • cyphar 9y ago
        Fair enough, though ultimately you could emulate it with sed: some-cmd | sed -E '{ s/^\s+//g ; s/\s+/ /g }' | cut -f$n
    • joosters 9y ago
      I wish the default 'cut' implementation could be just a little more clever - regex delimiters would be good, it doesn't even support multiple characters :( Also, cut's output manipulation is surprising. '-f 2,1' is actually the same as '-f 1,2' - you can't change the order of printing. I know there are other programs that can do the job, but it's a little frustrating when you can 'almost' get there with a chain of piped commands and a simple tool like cut, but have to fall back on a 'real' programming language to do just that extra bit of manipulation (awk, perl, whatever, and yes, I know the shell is a programming language but you get my point!)
      • cyphar 9y ago
        You mean to say you don't use some-cmd | sed -E 's/^\s+//;s/\s+/ /g' | cut -f$n Rather than some-cmd | awk '{ print $n }' ;) Also I agree it's silly you can't change the field order.
      • derriz 9y ago
        If you pipe your file through "while read f1 f2 f3 ; do echo field2 is $f2 ; done" for example you can pick out fields. Re-ordering them is just of a special case of any sort of bash manipulation you can do in the loop body. Admittedly for the very basic case, it's not as terse as "cut -f2" but if you're doing any further processing on the stream then I find it's often shorter.
        • 9y ago
  • kotokz 9y ago
    perl can do the same with -alne parms. but indeed awk has been widely used due to having this by default.