[cmake-developers] [CMake 0014195]: Document behavior of variable_watch on some built-in variables.

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://www.cmake.org/Bug/view.php?id=14195 
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Reported By:                Yichao Yu
Assigned To:                
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Project:                    CMake
Issue ID:                   14195
Category:                   Documentation
Reproducibility:            always
Severity:                   feature
Priority:                   normal
Status:                     new
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Date Submitted:             2013-06-04 06:16 EDT
Last Modified:              2013-06-04 06:16 EDT
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Summary:                    Document behavior of variable_watch on some built-in
variables.
Description: 
1, They are not mentioned anywhere, although it is really easy to tryout for a
specific version, it would be really nice to document the behaviors as well as
adding tests for them so that people can rely on them.

2, The specific variable I am interested in is CMAKE_PARENT_LIST_FILE (as well
as CMAKE_CURRENT_LIST_DIR, but this is introduced only in a recent version so it
is less interesting). This(These) variable(s) seems to be modified whenever
current list files changes (which makes sense) as well as when the main list
file is finished processing (which is the behavior that I cannot find a
documentation anywhere). The second behavior makes it a LOOOT easy to hook into
the end of configure stage in order to do sth that depends on the information
collected from the whole project, e.g. generate a command to extract doc/po from
all files in the project, or looks for "header files" that is generated within
the whole project for other languages (e.g. cython). I think it is a useful
feature (I've found emails asking how to do such thing...) and it will be really
nice to keep it as long as it is not so hard not to break it.

THX

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Issue History 
Date Modified    Username       Field                    Change               
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2013-06-04 06:16 Yichao Yu      New Issue                                    
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