diff options
Diffstat (limited to 'README.EXT')
| -rw-r--r-- | README.EXT | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/README.EXT b/README.EXT index 4cfe80bd82..e5d39911ca 100644 --- a/README.EXT +++ b/README.EXT @@ -330,17 +330,30 @@ of the innermost method (which is defined by Ruby) can be accessed. 2.2.2 ID or Symbol -You can invoke methods directly, without parsing the string. First I -need to explain about symbols (whose data type is ID). ID is the -integer number to represent Ruby's identifiers such as variable names. -It can be accessed from Ruby in the form: +You can invoke methods directly, without parsing the string. First I need +to explain about ID. ID is the integer number to represent Ruby's +identifiers such as variable names. The Ruby data type corresponding to ID +is Symbol. It can be accessed from Ruby in the form: :Identifier -You can get the symbol value from a string within C code by using +You can get the ID value from a string within C code by using rb_intern(const char *name) +You can retrieve ID from Ruby object (Symbol or String) given as an +argument by using + + rb_to_id(VALUE symbol) + +You can convert C ID to Ruby Symbol by using + + VALUE ID2SYM(ID id) + +and to convert Ruby Symbol object to ID, use + + ID SYM2ID(VALUE symbol) + 2.2.3 Invoke Ruby method from C To invoke methods directly, you can use the function below |