kevin lyda wrote:
> On Mon, Mar 25, 2002 at 05:05:39PM +0000, Padraig Brady wrote:
>>>Why?
>>>>sed -n -e "/[0-9]/p" testfile
>>>>is the same as:
>>>>grep "[0-9]" testfile
>>> no it's not if the file args are testfile1 and testfile2. and that's a
> good thing because if i'm editing files i don't want prefixes on the lines
> i'm playing with.
Again sed could easily default to printing filename prefixes if more
than one file specified.
> however for your example, they're both the same as:
>> awk '/[0-9]/{print}' testfile
>> or
>> perl -ne '/[0-9]/ && print' testfile
true
> or
>> while read l; do case "$l"; in *[0-9]*) echo "$l" ;; esac; done < testfile
don't be silly
> so should we roll the functionality of awk, perl and shell into sed?
err (don't be silly)^2, they're general purpose languages
> and you ignored my comment about complexity. to do a simple search you
> required two flags, two slashes and a p command. that's insane.
But one less command to know about.
> plus i don't see any docs concerning sed's return codes and what they
> mean - rather important in scripts that use grep.
again easy to change if they're not appropriate.
At this stage grep is obviously not going away,
but perhaps as a first stage you could merge sed/grep
to 1 binary, that behaves a little differently
depending on what argv[0] is, and also make
any (tiny) changes to sed to provide all of grep's
functionality.
>>>With a common function of finding a pattern.
>>> sometimes. you can also have sed add a boilerplate license at the top
> of each license file. no searching, just position. otoh, sometimes
> you just want grep to say the pattern exists, not to print it:
>> if grep -l foo bar > /dev/null 2>&1; then
> echo get a beer for foo
> else
> echo sing mournfully for foo
> fi
>>>>I think it's as easy for someone to learn the p command
>>in sed, as a seperate grep command. That just takes a
>>minute or two. The hard bit is understanding the regular
>>expressions.
>>> personally, i like anything that reduces typing.
>
personally I like nice narrow/general interfaces, which
is one of the things that makes UNIX so much nicer to
program than doze.
Padraig.
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