ceph/src/boost/tools/build/src/build/alias.jam

   1 # Copyright 2003, 2004, 2006 Vladimir Prus
   2 # Distributed under the Boost Software License, Version 1.0.
   3 # (See accompanying file LICENSE.txt or copy at
   4 # https://www.bfgroup.xyz/b2/LICENSE.txt)
   5
   6 # This module defines the 'alias' rule and the associated target class.
   7 #
   8 # Alias is just a main target which returns its source targets without any
   9 # processing. For example:
  10 #
  11 #   alias bin : hello test_hello ;
  12 #   alias lib : helpers xml_parser ;
  13 #
  14 # Another important use of 'alias' is to conveniently group source files:
  15 #
  16 #   alias platform-src : win.cpp : <os>NT ;
  17 #   alias platform-src : linux.cpp : <os>LINUX ;
  18 #   exe main : main.cpp platform-src ;
  19 #
  20 # Lastly, it is possible to create a local alias for some target, with different
  21 # properties:
  22 #
  23 #   alias big_lib : : @/external_project/big_lib/<link>static ;
  24 #
  25
  26 import "class" : new ;
  27 import param ;
  28 import project ;
  29 import property-set ;
  30 import targets ;
  31
  32
  33 class alias-target-class : basic-target
  34 {
  35     rule __init__ ( name : project : sources * : requirements *
  36         : default-build * : usage-requirements * )
  37     {
  38         basic-target.__init__ $(name) : $(project) : $(sources) :
  39             $(requirements) : $(default-build) : $(usage-requirements) ;
  40     }
  41
  42     rule construct ( name : source-targets * : property-set )
  43     {
  44         return [ property-set.empty ] $(source-targets) ;
  45     }
  46
  47     rule compute-usage-requirements ( subvariant )
  48     {
  49         local base = [ basic-target.compute-usage-requirements $(subvariant) ] ;
  50         return [ $(base).add [ $(subvariant).sources-usage-requirements ] ] ;
  51     }
  52
  53     rule skip-from-usage-requirements ( )
  54     {
  55     }
  56 }
  57
  58
  59 # Declares the 'alias' target. It will process its sources virtual-targets by
  60 # returning them unaltered as its own constructed virtual-targets.
  61 #
  62 rule alias ( name : sources * : requirements * : default-build * :
  63     usage-requirements * )
  64 {
  65     param.handle-named-params
  66         sources requirements default-build usage-requirements ;
  67
  68     local project = [ project.current ] ;
  69
  70     targets.main-target-alternative
  71         [ new alias-target-class $(name) : $(project)
  72             : [ targets.main-target-sources $(sources) : $(name) : no-renaming ]
  73             : [ targets.main-target-requirements $(requirements) : $(project) ]
  74             : [ targets.main-target-default-build $(default-build) : $(project)
  75                 ]
  76             : [ targets.main-target-usage-requirements $(usage-requirements) :
  77                 $(project) ]
  78         ] ;
  79 }
  80
  81
  82 IMPORT $(__name__) : alias : : alias ;