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Introduction
Mathematica's core tree-oriented symbolic language makes it well suited to working with a hierarchical view of C code as Mathematica expressions. This supports the use of the Mathematica language for the creation, manipulation, and optimization of C code.
It is used extensively for Mathematica's code generation tools. In addition, you can use SymbolicC for your own code manipulation purposes.
To use SymbolicC you first need to load the package.
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Now you can start to build up elements of a C program. The following represents a variable declaration.
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An important feature of SymbolicC expressions is that they are inert; they evaluate to themselves, staying in an unevaluated form.
Here is an assignment and an entire function.
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You can keep the function as an expression, or you can convert it into a string that shows the C code.
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Importing from C Programs
At present Mathematica has no feature for importing from C programs. This has a number of challenges, such as how to work with the C preprocessor and dealing with context-sensitive parsing. Despite this, SymbolicC is very useful as a way to create C programs.
The C preprocessor adds difficulties, because it is appealing to represent it in SymbolicC, but there are programs that are hard to represent in a strict tree fashion. An example is shown below.
#ifdef __cplusplus
extern "C" {
#endif
int function( int arg);
#ifdef __cplusplus
}
#endif
To parse the C language you need to understand the meaning and context of the input. For example, in the following it is not clear whether this is a declaration of b, which is a pointer to type a, or a multiplication of two variables, a and b.
a * b
