in m4's patsubst, how do I replace newlines with spaces?

m4, makefile, preprocessor, regex

Solution

patsubst(MULTI_LINE_STR_DEFINE,`
',` ')

That is, you put the newline, literally, between quotes.

Problem

How can I tell m4's `patsubstr` to replace all newlines in a string with a space? I've tried: ``` patsubst(MULTI_LINE_STR_DEFINE,`\n',` ') ``` and ``` patsubst(MULTI_LINE_STR_DEFINE,`\\n',` ') ```

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