[CMake] Undocumented magic required for installing globbed files

[Radu Serban]

Alan W. Irwin wrote:

> install(
>   CODE "
>   file(GLOB USER_DOCS ${CMAKE_SOURCE_DIR}/doc/user/html/*) \n
>   file(INSTALL DESTINATION ${docdir}/html/user/html
>   TYPE FILE FILES \${USER_DOCS}
>   )"
> )
[snip]
> Furthermore, I have no clue why the $ in ${USER_DOCS} has to be escaped, 
> but
> the other "$" within the file commands do not.  So all this seems very much
> like magic to me in the absence of documentation.
> 

My guess: If the last $ were not escaped, cmake would attempt to expand it to 
its value in the CMakeLists.txt script (where it is not defined). I assume that 
the INSTALL CODE signature generates a CMake script on the fly which in your 
case will be:

file(GLOB USER_DOCS path_to_sources/doc/user/html/*)
file(INSTALL DESTINATION path_to_docdir/html/user/html
   TYPE FILE FILES ${USER_DOCS})

where path_to_sources is whatever CMAKE_SOURCE_DIR was in your CMakeLists.txt 
(similarly path_to_docdir is whatever ${docdir} was there). Now, if you were to 
run this script, USER_DOCS will contain the proper list of files.


Just out of curiosity, is there any reason/advantage to using the above versus 
simply having

file(GLOB USER_DOCS ${CMAKE_SOURCE_SIR}/doc/user/html/*)
file(INSTALL DESTINATION ${docdir}/html/user/html
   TYPE FILE FILES ${USER_DOCS})

--Radu