AM_CONDITIONAL + AM_COND_IF does not work

[Marc Wäckerlin]

According to the official documentation(*):
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Here is an example of how to define a conditional config file:
AM_CONDITIONAL([SHELL_WRAPPER], [test "x$with_wrapper" = xtrue])
AM_COND_IF([SHELL_WRAPPER],
           [AC_CONFIG_FILES([wrapper:wrapper.in])])
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I try to generically find out, whether examples/makefile.am exists in a 
project and to automatically use it, if it exists:
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AM_CONDITIONAL([HAVE_EXAMPLES_DIR], [test -f examples/makefile.am])
AM_COND_IF([HAVE_EXAMPLES_DIR], [AC_CONFIG_FILES([examples/makefile])])
------------------------------------------

But automake fails:
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configure.ac:27: error: required file 'examples/makefile.in' not found
------------------------------------------

So, what's the problem?

It's nearly the same code as in the example ...



(*) see 
http://www.gnu.org/software/automake/manual/html_node/Usage-of-Conditionals.html

Thank you
Regards
Marc
--
Marc Wäckerlin