diff -ur docoptcpp-0.6.2/meson.build docoptcpp-0.6.2_boostregex/meson.build
--- docoptcpp-0.6.2/meson.build	2024-08-28 17:22:46.256716100 +0200
+++ docoptcpp-0.6.2_boostregex/meson.build	2024-08-28 17:02:47.932681000 +0200
@@ -8,6 +8,10 @@
   add_project_arguments('-DDOCOPT_DLL', '-DDOCOPT_EXPORTS', language: 'cpp')
 endif
 
+if cpp.get_id() =='msvc'
+  add_project_arguments('-DDOCTOPT_USE_BOOST_REGEX', '-DBOOST_REGEX_STANDALONE', language: 'cpp')
+endif
+
 # bug with missing dllexport. fixed in next version.
 if cpp.get_argument_syntax() == 'msvc'
   doclib = static_library('docopt', 'docopt.cpp', install: true)