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jpayne@68: While cairo is implemented and C, and has a C API, it is expected jpayne@68: that many users of cairo will be using it from languages other jpayne@68: than C. The glue that connects the core cairo library to another jpayne@68: language is known as a language jpayne@68: binding. This appendix attempts to collect together jpayne@68: issues that come up when creating a language bindings for cairo jpayne@68: and present standardized solutions to promote consistency among jpayne@68: the different language bindings. jpayne@68:
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jpayne@68: The naming of the central cairo_t type is a
jpayne@68: special exception. The object is “a cairo context” not “a
jpayne@68: cairo”, and names such as cairo_t rather than
jpayne@68: cairo_context_t and
jpayne@68: cairo_set_source() rather than
jpayne@68: cairo_context_set_source() are simply
jpayne@68: abbreviations to make the C API more palatable. In languages
jpayne@68: which have object-oriented syntax, this abbreviation is much
jpayne@68: less useful. In fact, if ‘Cairo’ is used as a namespace, then
jpayne@68: in many languages, you'd end up with a ridiculous type name
jpayne@68: like ‘Cairo.Cairo’. For this reason, and for inter-language
jpayne@68: consistency all object-oriented languages should name this
jpayne@68: type as if it were cairo_context_t.
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jpayne@68: The punctuation and casing of the type names and
jpayne@68: method names of cairo should be changed to match the general
jpayne@68: convention of the language. In Java, where type names are written
jpayne@68: in StudlyCaps and method names in javaCaps, cairo_font_extents_t
jpayne@68: will become FontExtents and
jpayne@68: cairo_set_source(cr,source),
jpayne@68: cr.setSource(source).
jpayne@68: As compared to changing the punctuation, and casing, much
jpayne@68: more reluctance should be used in changing the method names
jpayne@68: themselves. Even if get is usually omitted from getters in
jpayne@68: your language, you shouldn't bind cairo_get_source() as
jpayne@68: cr.source().
jpayne@68: