tests: [WIP] add unit tests for some of the instructions

Signed-off-by: Amneesh Singh <natto@weirdnatto.in>

meson.build

@@ -3,10 +3,32 @@ project('matar', 'cpp',
   license : 'GPLv3',
   default_options : ['warning_level=3',
                      'werror=true',
-                     'optimization=3',
-                     'cpp_std=c++20'])
+                     'optimization=3'])
+
+compiler = meson.get_compiler('cpp')
+
+if compiler.has_argument('-std=c++23')
+  add_global_arguments('-std=c++23', language: 'cpp')
+elif compiler.has_argument('-std=c++2b')
+  add_global_arguments('-std=c++2b', language: 'cpp')
+else
+  error(compiler.get_id() + ' ' + compiler.version() + 'does not meet the compiler requirements')
+endif
+
+'''
+TODO: use <print> and <format> instead of libfmt once LLVM 17 is out
+
+if compiler.has_argument('-fexperimental-library')
+  add_global_arguments('-fexperimental-library', language: 'cpp')
+else
+  error(compiler.get_id() + ' ' + compiler.version() + 'does not support -fexperimental-library')
+endif
+'''
 
 inc = include_directories('include')
+
 subdir('include')
 subdir('src')
 subdir('apps')
+
+subdir('tests')