diff options
Diffstat (limited to 'doc/manual/ffi.txt')
| -rw-r--r-- | doc/manual/ffi.txt | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/doc/manual/ffi.txt b/doc/manual/ffi.txt index 5055f18af..d7d9596d2 100644 --- a/doc/manual/ffi.txt +++ b/doc/manual/ffi.txt @@ -16,12 +16,20 @@ spelled*: .. code-block:: proc printf(formatstr: cstring) {.header: "<stdio.h>", importc: "printf", varargs.} -Note that this pragma is somewhat of a misnomer: Other backends will provide +Note that this pragma is somewhat of a misnomer: Other backends do provide the same feature under the same name. Also, if one is interfacing with C++ the `ImportCpp pragma <manual.html#implementation-specific-pragmas-importcpp-pragma>`_ and interfacing with Objective-C the `ImportObjC pragma <manual.html#implementation-specific-pragmas-importobjc-pragma>`_ can be used. +The string literal passed to ``importc`` can be a format string: + +.. code-block:: Nim + proc p(s: cstring) {.importc: "prefix$1".} + +In the example the external name of ``p`` is set to ``prefixp``. Only ``$1`` +is available and a literal dollar sign must be written as ``$$``. + Exportc pragma -------------- @@ -33,9 +41,19 @@ name is the Nim identifier *exactly as spelled*: .. code-block:: Nim proc callme(formatstr: cstring) {.exportc: "callMe", varargs.} -Note that this pragma is somewhat of a misnomer: Other backends will provide +Note that this pragma is somewhat of a misnomer: Other backends do provide the same feature under the same name. +The string literal passed to ``exportc`` can be a format string: + +.. code-block:: Nim + proc p(s: string) {.exportc: "prefix$1".} = + echo s + +In the example the external name of ``p`` is set to ``prefixp``. Only ``$1`` +is available and a literal dollar sign must be written as ``$$``. + + Extern pragma ------------- @@ -46,7 +64,9 @@ mangling. The string literal passed to ``extern`` can be a format string: proc p(s: string) {.extern: "prefix$1".} = echo s -In the example the external name of ``p`` is set to ``prefixp``. +In the example the external name of ``p`` is set to ``prefixp``. Only ``$1`` +is available and a literal dollar sign must be written as ``$$``. + Bycopy pragma |