interpreter: add required and disabled to import

This is useful both from the perspective of optional functionality that
requires a module, and also as I continue to progress with Meson++,
which will probably not implement all of the modules that Meson itself
does.

2 files changed, 20 insertions, 5 deletions

diff --git a/docs/markdown/Reference-manual.md b/docs/markdown/Reference-manual.md
index 16fcbbf..e96a6fc 100644
--- a/docs/markdown/Reference-manual.md
+++ b/docs/markdown/Reference-manual.md
@@ -973,19 +973,21 @@ a non-existing variable will cause a fatal error.
 
 ### import()
 
-``` meson
-    module_object import(module_name)
+```
+  module_object import(string, required : bool | feature, disabler : bool)
 ```
 
-Imports the given extension module. Returns an opaque object that can
-be used to call the methods of the module. Here's an example for a
-hypothetical `testmod` module.
+Imports the given extension module. Returns an object that can be used to call
+the methods of the module. Here's an example for a hypothetical `testmod`
+module.
 
 ```meson
     tmod = import('testmod')
     tmod.do_something()
 ```
 
+*Since 0.59.0* the required and disabler keyword arguments
+
 ### include_directories()
 
 ``` meson
@@ -2911,3 +2913,11 @@ sample piece of code with [`compiler.run()`](#compiler-object) or
 - `returncode()`: the return code of executing the compiled binary
 - `stderr()`: the standard error produced when the command was run
 - `stdout()`: the standard out produced when the command was run
+
+### `module` object
+
+Modules provide their own specific implementation methods, but all modules
+proivide the following methods:
+
+- `bool found()`: returns True if the module was successfully imported,
+  otherwise false. *Since 0.59.0*
diff --git a/docs/markdown/snippets/required_and_disabled_import.md b/docs/markdown/snippets/required_and_disabled_import.md
new file mode 100644
index 0000000..39ca307
--- /dev/null
+++ b/docs/markdown/snippets/required_and_disabled_import.md
@@ -0,0 +1,5 @@
+## The `import()` function gains `required` and `disabler` arguments
+
+In addition, modules now have a `found()` method, like programs and
+dependencies. This allows them to be conditionally required, and used in most
+places that an object with a `found()` method can be.