Tooling.rst source code [clang_source

1	=================================================
2	Choosing the Right Interface for Your Application
3	=================================================
4
5	Clang provides infrastructure to write tools that need syntactic and semantic
6	information about a program. This document will give a short introduction of
7	the different ways to write clang tools, and their pros and cons.
8
9	LibClang
10	--------
11
12	`LibClang <https://clang.llvm.org/doxygen/group__CINDEX.html>`_ is a stable high
13	level C interface to clang. When in doubt LibClang is probably the interface
14	you want to use. Consider the other interfaces only when you have a good
15	reason not to use LibClang.
16
17	Canonical examples of when to use LibClang:
18
19	* Xcode
20	* Clang Python Bindings
21
22	Use LibClang when you...:
23
24	* want to interface with clang from other languages than C++
25	* need a stable interface that takes care to be backwards compatible
26	* want powerful high-level abstractions, like iterating through an AST with a
27	cursor, and don't want to learn all the nitty gritty details of Clang's AST.
28
29	Do not use LibClang when you...:
30
31	* want full control over the Clang AST
32
33	Clang Plugins
34	-------------
35
36	:doc:`Clang Plugins <ClangPlugins>` allow you to run additional actions on the
37	AST as part of a compilation. Plugins are dynamic libraries that are loaded at
38	runtime by the compiler, and they're easy to integrate into your build
39	environment.
40
41	Canonical examples of when to use Clang Plugins:
42
43	* special lint-style warnings or errors for your project
44	* creating additional build artifacts from a single compile step
45
46	Use Clang Plugins when you...:
47
48	* need your tool to rerun if any of the dependencies change
49	* want your tool to make or break a build
50	* need full control over the Clang AST
51
52	Do not use Clang Plugins when you...:
53
54	* want to run tools outside of your build environment
55	* want full control on how Clang is set up, including mapping of in-memory
56	virtual files
57	* need to run over a specific subset of files in your project which is not
58	necessarily related to any changes which would trigger rebuilds
59
60	LibTooling
61	----------
62
63	:doc:`LibTooling <LibTooling>` is a C++ interface aimed at writing standalone
64	tools, as well as integrating into services that run clang tools. Canonical
65	examples of when to use LibTooling:
66
67	* a simple syntax checker
68	* refactoring tools
69
70	Use LibTooling when you...:
71
72	* want to run tools over a single file, or a specific subset of files,
73	independently of the build system
74	* want full control over the Clang AST
75	* want to share code with Clang Plugins
76
77	Do not use LibTooling when you...:
78
79	* want to run as part of the build triggered by dependency changes
80	* want a stable interface so you don't need to change your code when the AST API
81	changes
82	* want high level abstractions like cursors and code completion out of the box
83	* do not want to write your tools in C++
84
85	:doc:`Clang tools <ClangTools>` are a collection of specific developer tools
86	built on top of the LibTooling infrastructure as part of the Clang project.
87	They are targeted at automating and improving core development activities of
88	C/C++ developers.
89
90	Examples of tools we are building or planning as part of the Clang project:
91
92	* Syntax checking (:program:`clang-check`)
93	* Automatic fixing of compile errors (:program:`clang-fixit`)
94	* Automatic code formatting (:program:`clang-format`)
95	* Migration tools for new features in new language standards
96	* Core refactoring tools
97
98

Clang Project