Add support for modular build structure. (#218)

* Make the library modular usable.

* Switch to library requirements instead of source. As source puts extra source in install targets.

* Add missing NO_LIB usage requirements.

* Add requires-b2 check to top-level build file.

* Update dependencies.

* Bump B2 require to 5.2

* Move inter-lib dependencies to a project variable and into the build targets.

build.jam

@@ -0,0 +1,26 @@
+# Copyright René Ferdinand Rivera Morell 2024
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or copy at
+# http://www.boost.org/LICENSE_1_0.txt)
+
+require-b2 5.2 ;
+
+constant boost_dependencies :
+    /boost/assert//boost_assert
+    /boost/config//boost_config
+    /boost/core//boost_core ;
+
+project /boost/charconv
+    : common-requirements
+        <include>include
+    ;
+
+explicit
+    [ alias boost_charconv : build//boost_charconv ]
+    [ alias all : boost_charconv test ]
+    ;
+
+call-if : boost-library charconv
+    : install boost_charconv
+    ;
+

build/Jamfile

@@ -3,9 +3,12 @@
 # Distributed under the Boost Software License, Version 1.0.
 # https://www.boost.org/LICENSE_1_0.txt
 
-import ../../config/checks/config : requires ;
+require-b2 5.0.1 ;
+import-search /boost/config/checks ;
 
-project boost/charconv ;
+import config : requires ;
+
+project : common-requirements <library>$(boost_dependencies) ;
 
 local SOURCES = from_chars.cpp to_chars.cpp ;
 
@@ -28,6 +31,5 @@ lib boost_charconv
 
   # usage-requirements
   : <link>shared:<define>BOOST_CHARCONV_DYN_LINK=1
+    <define>BOOST_CHARCONV_NO_LIB=1
 ;
-
-boost-install boost_charconv ;

test/Jamfile

@@ -3,8 +3,11 @@
 # Distributed under the Boost Software License, Version 1.0.
 # https://www.boost.org/LICENSE_1_0.txt
 
+require-b2 5.0.1 ;
+import-search /boost/config/checks ;
+
 import testing ;
-import ../../config/checks/config : requires ;
+import config : requires ;
 
 project : requirements
 
@@ -58,7 +61,7 @@ run P2497.cpp ;
 run github_issue_110.cpp ;
 run github_issue_122.cpp ;
 run from_chars_string_view.cpp ;
-run github_issue_152.cpp ;
+run github_issue_152.cpp /boost/random//boost_random ;
 run github_issue_152_float128.cpp : : : [ check-target-builds ../config//has_float128 "GCC libquadmath and __float128 support" : <library>"quadmath" ] ;
 run github_issue_154.cpp ;
 #run github_issue_156.cpp ;