add build option to disable repl, use feature objects

README.md

@@ -73,8 +73,8 @@ utilized in the outside native code.
 There are no dependencies (other than a suitable compiler and the standard
 library).
 
-Libostd is built using Meson. Therefore, you need to install Meson and then
-you can compile it as usual. Typically, this will be something like
+Libcubescript is built using `meson`. After installing it, you can do
+something like this:
 
 ~~~
 mkdir build && cd build
@@ -82,15 +82,22 @@ meson ..
 ninja all
 ~~~
 
-Link the libcubescript library together with your application and everything
-should just work. It also builds the REPL.
+Link the `libcubescript` library together with your application and everything
+should just work. It also builds the REPL by default.
 
-The project also bundles the linenoise line editing library which has been
-modified to compile cleanly as C++ (with the same flags as libcubescript).
+The project also bundles the `linenoise` line editing library which has been
+modified to compile cleanly as C++ (with the same flags as `libcubescript`).
 It's used strictly for the REPL only (you don't need it to build libcubescript
 itself). The version in the repository tracks Git revision
 https://github.com/antirez/linenoise/commit/c894b9e59f02203dbe4e2be657572cf88c4230c3.
 
+For the REPL (when not disabled with `-Drepl=disabled`) you have a choice of
+two line editing libraries. The `readline` library can be used (but is always
+disabled by default, so you need to enable it manually). On Unix-like systems,
+`linenoise` can be used (and is fully featured) and is enabled by default; on
+Windows it's disabled. There is also a fallback without any line editing, used
+when you don't have either (but then there is no line editing or history).
+
 ## Licensing
 
 See COPYING.md for licensing information.

meson_options.txt

@@ -1,11 +1,17 @@
+option('repl',
+    type: 'feature',
+    value: 'auto',
+    description: 'Enable the REPL (command line tool)'
+)
+
 option('readline',
-    type: 'boolean',
-    value: false,
+    type: 'feature',
+    value: 'auto',
     description: 'Use GNU readline for the REPL'
 )
 
 option('linenoise',
-    type: 'boolean',
-    value: true,
+    type: 'feature',
+    value: 'auto',
     description: 'Use linenoise for the REPL'
 )

tools/meson.build

@@ -5,18 +5,30 @@ repl_src = [
 repl_deps = [libcubescript]
 repl_flags = []
 
-if get_option('readline')
-    repl_deps += [dependency('readline')]
-    repl_flags = ['-DCS_REPL_USE_READLINE']
-elif get_option('linenoise')
-    repl_src += ['linenoise.cc']
-    repl_flags = ['-DCS_REPL_USE_LINENOISE']
+if get_option('readline').enabled()
+    use_readline = true
+    use_linenoise = false
+elif get_option('linenoise').enabled()
+    use_readline = false
+    use_linenoise = true
+elif get_option('linenoise').auto()
+    use_readline = false
+    use_linenoise = (host_machine.system() != 'windows')
 endif
 
-executable('cubescript',
-    repl_src,
-    dependencies: repl_deps,
-    include_directories: libcubescript_includes + [include_directories('.')],
-    cpp_args: extra_cxxflags + repl_flags,
-    install: true
-)
+if not get_option('repl').disabled()
+    if use_readline
+        repl_deps += [dependency('readline')]
+        repl_flags = ['-DCS_REPL_USE_READLINE']
+    elif use_linenoise
+        repl_src += ['linenoise.cc']
+        repl_flags = ['-DCS_REPL_USE_LINENOISE']
+    endif
+    executable('cubescript',
+        repl_src,
+        dependencies: repl_deps,
+        include_directories: libcubescript_includes + [include_directories('.')],
+        cpp_args: extra_cxxflags + repl_flags,
+        install: true
+    )
+endif