Inspired by a recent SoPW, how short can you write a diff of two simple csv files that displays the missing keys from the two files prefixed by the fileno they were missing from?

Some test data: 

P:\test>type t1.csv
1,the,rest
2,the,rest
3,the,rest
4,the,rest
5,the,rest

P:\test>type t2.csv
2,the,rest
4,the,rest
6,the,rest
8,the,rest

[download]

And my best that at 114 strokes can surely be well beaten?

Rules: Command, including all switches count; filenames don't. 

# 23456789 123456789 123456789 123456789 123456789 123456789 123456789
+ 123456789 123456789 123456789 123456789 1234
perl -anF, -le"$h{$F[0]}=1;eof&&last}{$h{(split',',$_)[0]}--while<>;$h
+{$_}&&print $h{$_}<0?'1:':'2:',$_ for keys%h" t1.csv t2.csv
1:8
1:6
2:1
2:3
2:5

[download]
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

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Re: [GOLF] Perl csv diff
by truedfx (Monk) on Nov 03, 2005 at 13:25 UTC
    Here's a quick one in 84 (updated from 86 because I had a pointless !! before eof) (unless I miscounted) -- relying on $^F defaulting to 2: 
    #--------1---------2---------3---------4---------5---------6---------7
+---------8--------
#234567890123456789012345678901234567890123456789012345678901234567890
+123456789012345678
perl -anF, -le'$h{$F[0]}|=$^F;$^F-=eof}{"@_"=~/[12]$/&&print"$&:$`"whi
+le(@_=each%h)' t1.csv t2.csv
1:8 
1:6 
2:1 
2:3 
2:5

    [download]
    As always with hashes, I can't promise anything about the order of the output, but that seems to be okay. :)

    Update:
    79, by using 2-@ARGV instead of $^F
    78, by using the implicit print from -p
    77, by splitting manually instead of with -a 
    #--------1---------2---------3---------4---------5---------6---------7
+-------
#234567890123456789012345678901234567890123456789012345678901234567890
+1234567
perl -pe'@h{/([^,]*)/}|=2-@ARGV}while(@_=each%h){$_="@_"=~/[12]$/&&"$&
+:$`$/"'

    [download]
[reply]
[d/l]
[select]

      That's neat! I had to run away to perlvar to work out what $^F was. Uniquely for a while now, I had absolutely no idea.

      That is a genuinely perverse piece of lateral thinking. ++.

      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]

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