🚀 go-pugleaf

In article <726603701.528921.BNB@MATH.AMS.ORG>, BNB@MATH.AMS.ORG (bbeeton) writes:
|> 
|> take a simpler example:
|>     \newcount\num
|>     \def\newnum#1#2.{\num=#1 \def\rest{#2}}
|>     \newnum12345.
|> this will end up with \num=12345 and \rest empty (with a delimited
|> string, the part between delimiters need not contain anything).

Ahem. No it won't. The splitting into '1' and '2345' occurs at macro
argument parsing time, and is no different for this fragment than in
the one you give later:

|>     \newcount\num
|>     \def\newnum#1#2.{\def\xnum{#1}\num=\xnum \def\rest{#2}}
|>     \newnum12345.

You are thinking of some case when the assignment is seeing the whole
string of digits and will gobble as many as it can, e.g.

       \newcount\num
       \def\newnum{\afterassignment\newnumrest \num=}
       \def\newnumrest#1.{\def\rest{#1}}
       \newnum12345.

Chris Thompson
Cambridge University Computing Service
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