Re: Bug in M4

[Andreas Schwab]

"Sam Lauber" <address@hidden> writes:

> I was using GNU M4 1.4.2, and typed in the following recursive additive macro:
>
> define(`add', `ifelse($1, 0, $2, add(decr($1), incr($2))')
>
> I then typed `add(1, 1)'. Obviously, I expected it to say `2', but it said
>
> `Recursion limit of 250 exceeded; use -L<N> to change'
>
> I consider this a bug,

It is, in your macro.  Fix the quoting and paren nesting.

define(`add', `ifelse($1, 0, `$2', `add(decr($1), incr($2))')')

Andreas.

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Andreas Schwab, SuSE Labs, address@hidden
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