3 <title>SWIG Parameter Handling</title>
8 <h1>SWIG Parameter Handling</h1>
12 dave-swig@dabeaz.com<br>
20 This document describes the functions related to management of function parameters and parameter lists in the SWIG core. These functions are declared in <tt>Source/Swig/swigparm.h</tt>. This API is considered to be stable.
24 The following utility functions are used to create and copy individual parameters. In their most basic form, a parameter merely contains a type, a name, and an optional default value.
27 <b><tt>Parm *NewParm(SwigType *type, const String_or_char *name)</tt></b>
30 Creates a new parameter object with type <tt>type</tt> and name <tt>name</tt>. The type is stored in the attribute "type" and the name is stored in the attribute "name".
34 <b><tt>Parm *CopyParm(Parm *p)</tt></b>
36 Copies a parameter object. All string attributes are copied in the
37 process of making the copy. However, no complex attributes (lists,
38 hashes, etc.) are copied.
41 <h2>Parameter Lists</h2>
44 <b><tt>ParmList *CopyParmList(ParmList *p)</tt></b>
46 Creates a copy of a parameter list. A parameter list is merely a linked list of parameters created by NewParm().
50 <b><tt>ParmList *CopyParmListMax(ParmList *p, int count)</tt></b>
52 Copies at most <tt>count</tt> parameters from the parameter list <tt>p</tt>.
56 <b><tt>int ParmList_len(ParmList *p)</tt></b>
59 Returns the total number of parameters in a parameter list.
63 <b><tt>int ParmList_numrequired(ParmList *p)</tt></b>
65 Returns the number of required parameters in a parameter list. This pertains to invoking a function/method in C/C++.
69 <b><tt>int ParmList_has_defaultargs(ParmList *p)</tt></b>
71 Returns 1 if the parameter list has any default arguments. Otherwise returns 0.
75 <h2>Code Generation Functions</h2>
78 <b><tt>String *ParmList_str(ParmList *p)</tt></b>
80 Creates a C prototype string of the parameters, but without any default values.
84 <b><tt>String *ParmList_str_defaultargs(ParmList *p)</tt></b>
86 Creates a C prototype string of the parameters and includes the default values (if any).
90 <b><tt>String *ParmList_protostr(ParmList *p)</tt></b>
92 Creates a C prototype string of the parameters.