Re: M4 problem with escaping macro arguments

[Andreas Schwab]

address@hidden (Chris Leishman) writes:

|> Hi all,
|> 
|> According to the info page:
|> 
|>  If you want a macro to expand to something like `$12', put a pair of
|>  quotes after the `$'.  This will prevent `m4' from interpreting the `$'
|>  sign as a reference to an argument.
|> 
|> However, with gnu m4 version 1.4, the following results are observed:
|> 
|> $ m4 --version
|> GNU m4 1.4
|> $ echo "define(y, \$1-\$\`'2)y(5,6)"
|> define(y, $1-$`'2)y(5,6)
|> $ echo "define(y, \$1-\$\`'2)y(5,6)" | m4

This is not correctly quoted:

$ echo "define(y, \$1-\$\`'2)y(5,6)" | m4 -dtaeq
m4trace: -1- define(`y', `$1-$2')
m4trace: -1- y(`5', `6') -> `5-6'
5-6
$ echo "define(\`y', \`\$1-\$\`'2')y(5,6)" | m4 -dtaeq
m4trace: -1- define(`y', `$1-$`'2')
m4trace: -1- y(`5', `6') -> `5-$`'2'
5-$2

Andreas.

-- 
Andreas Schwab                                  "And now for something
SuSE Labs                                        completely different."
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