Tcl_CreateMathFunc - Define, query and enumerate math functions for expressions
#include <tcl.h> void Tcl_CreateMathFunc(interp, name, numArgs, argTypes, proc, clientData) int Tcl_GetMathFuncInfo(interp, name, numArgsPtr, argTypesPtr, procPtr, clientDataPtr) Tcl_Obj * Tcl_ListMathFuncs(interp, pattern)
Tcl_CreateMathFunc(3tcl) Tcl Library Procedures Tcl_CreateMathFunc(3tcl)
______________________________________________________________________________
NAME
Tcl_CreateMathFunc, Tcl_GetMathFuncInfo, Tcl_ListMathFuncs - Define,
query and enumerate math functions for expressions
NOTICE OF EVENTUAL DEPRECATION
The Tcl_CreateMathFunc and Tcl_GetMathFuncInfo functions are rendered
somewhat obsolete by the ability to create functions for expressions by
placing commands in the tcl::mathfunc namespace, as described in the
mathfunc manual page; the API described on this page is not expected to
be maintained indefinitely.
SYNOPSIS
#include <tcl.h>
void
Tcl_CreateMathFunc(interp, name, numArgs, argTypes, proc, clientData)
int
Tcl_GetMathFuncInfo(interp, name, numArgsPtr, argTypesPtr, procPtr,
clientDataPtr)
Tcl_Obj *
Tcl_ListMathFuncs(interp, pattern)
ARGUMENTS
Tcl_Interp *interp (in) Interpreter in which new
function will be defined.
const char *name (in) Name for new function.
int numArgs (in) Number of arguments to new
function; also gives size
of argTypes array.
Tcl_ValueType *argTypes (in) Points to an array giving
the permissible types for
each argument to function.
Tcl_MathProc *proc (in) Procedure that implements
the function.
ClientData clientData (in) Arbitrary one-word value to
pass to proc when it is
invoked.
int *numArgsPtr (out) Points to a variable that
will be set to contain the
number of arguments to the
function.
Tcl_ValueType **argTypesPtr (out) Points to a variable that
will be set to contain a
pointer to an array giving
the permissible types for
each argument to the func-
tion which will need to be
freed up using Tcl_Free.
Tcl_MathProc **procPtr (out) Points to a variable that
will be set to contain a
pointer to the implementa-
tion code for the function
(or NULL if the function is
implemented directly in
bytecode).
ClientData *clientDataPtr (out) Points to a variable that
will be set to contain the
clientData argument passed
to Tcl_CreateMathFunc when
the function was created if
the function is not imple-
mented directly in bytecode.
const char *pattern (in) Pattern to match against
function names so as to fil-
ter them (by passing to
Tcl_StringMatch), or NULL to
not apply any filter.
______________________________________________________________________________
DESCRIPTION
Tcl allows a number of mathematical functions to be used in expres-
sions, such as sin, cos, and hypot. These functions are represented by
commands in the namespace, tcl::mathfunc. The Tcl_CreateMathFunc func-
tion is an obsolete way for applications to add additional functions to
those already provided by Tcl or to replace existing functions. It
should not be used by new applications, which should create math func-
tions using Tcl_CreateObjCommand to create a command in the tcl::math-
func namespace.
In the Tcl_CreateMathFunc interface, Name is the name of the function
as it will appear in expressions. If name does not already exist in
the ::tcl::mathfunc namespace, then a new command is created in that
namespace. If name does exist, then the existing function is replaced.
NumArgs and argTypes describe the arguments to the function. Each
entry in the argTypes array must be one of TCL_INT, TCL_DOUBLE,
TCL_WIDE_INT, or TCL_EITHER to indicate whether the corresponding argu-
ment must be an integer, a double-precision floating value, a wide
(64-bit) integer, or any, respectively.
Whenever the function is invoked in an expression Tcl will invoke proc.
Proc should have arguments and result that match the type Tcl_MathProc:
typedef int Tcl_MathProc(
ClientData clientData,
Tcl_Interp *interp,
Tcl_Value *args,
Tcl_Value *resultPtr);
When proc is invoked the clientData and interp arguments will be the
same as those passed to Tcl_CreateMathFunc. Args will point to an
array of numArgs Tcl_Value structures, which describe the actual argu-
ments to the function:
typedef struct Tcl_Value {
Tcl_ValueType type;
long intValue;
double doubleValue;
Tcl_WideInt wideValue;
} Tcl_Value;
The type field indicates the type of the argument and is one of
TCL_INT, TCL_DOUBLE or TCL_WIDE_INT. It will match the argTypes value
specified for the function unless the argTypes value was TCL_EITHER.
Tcl converts the argument supplied in the expression to the type
requested in argTypes, if that is necessary. Depending on the value of
the type field, the intValue, doubleValue or wideValue field will con-
tain the actual value of the argument.
Proc should compute its result and store it either as an integer in
resultPtr->intValue or as a floating value in resultPtr->doubleValue.
It should set also resultPtr->type to one of TCL_INT, TCL_DOUBLE or
TCL_WIDE_INT to indicate which value was set. Under normal circum-
stances proc should return TCL_OK. If an error occurs while executing
the function, proc should return TCL_ERROR and leave an error message
in the interpreter's result.
Tcl_GetMathFuncInfo retrieves the values associated with function name
that were passed to a preceding Tcl_CreateMathFunc call. Normally, the
return code is TCL_OK but if the named function does not exist,
TCL_ERROR is returned and an error message is placed in the inter-
preter's result.
If an error did not occur, the array reference placed in the variable
pointed to by argTypesPtr is newly allocated, and should be released by
passing it to Tcl_Free. Some functions (the standard set implemented
in the core, and those defined by placing commands in the tcl::mathfunc
namespace) do not have argument type information; attempting to
retrieve values for them causes a NULL to be stored in the variable
pointed to by procPtr and the variable pointed to by clientDataPtr will
not be modified. The variable pointed to by numArgsPointer will con-
tain -1, and no argument types will be stored in the variable pointed
to by argTypesPointer.
Tcl_ListMathFuncs returns a Tcl value containing a list of all the math
functions defined in the interpreter whose name matches pattern. The
returned value has a reference count of zero.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | runtime/tcl-8 |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
expr(n), info(n), Tcl_CreateObjCommand(3), Tcl_Free(3), Tcl_NewLis-
tObj(3)
KEYWORDS
expression, mathematical function
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from http://prdownloads.sourceforge.net/tcl/tcl-
core8.6.7-src.tar.gz.
Further information about this software can be found on the open source
community website at https://www.tcl.tk/.
Tcl 8.4 Tcl_CreateMathFunc(3tcl)