Tcl_DoubleObj(3) Tcl (8.0) Tcl_DoubleObj(3)
_________________________________________________________________
NAME
Tcl_NewDoubleObj, Tcl_SetDoubleObj, Tcl_GetDoubleFromObj -
manipulate Tcl objects as floating-point values
SYNOPSIS
#include <tcl.h>
Tcl_Obj *
Tcl_NewDoubleObj(doubleValue)
Tcl_SetDoubleObj(objPtr, doubleValue)
int
Tcl_GetDoubleFromObj(interp, objPtr, doublePtr)
ARGUMENTS
double doubleValue (in) A double-precision
floating point value
used to initialize or
set a double object.
Tcl_Obj *objPtr (in/out) For Tcl_SetDoubleObj,
this points to the
object to be converted
to double type. For
Tcl_GetDoubleFromObj,
this refers to the
object from which to
get a double value; if
objPtr does not already
point to a double
object, an attempt will
be made to convert it
to one.
Tcl_Interp *interp (in/out) If an error occurs
during conversion, an
error message is left
in the interpreter's
result object unless
interp is NULL.
double *doublePtr (out) Points to place to
store the double value
obtained from objPtr.
_________________________________________________________________
DESCRIPTION
These procedures are used to create, modify, and read double
Page 1 (printed 2/19/99)
Tcl_DoubleObj(3) Tcl (8.0) Tcl_DoubleObj(3)
Tcl objects from C code. Tcl_NewDoubleObj and
Tcl_SetDoubleObj will create a new object of double type or
modify an existing object to have double type. Both of these
procedures set the object to have the double-precision
floating point value given by doubleValue; Tcl_NewDoubleObj
returns a pointer to a newly created object with reference
count zero. Both procedures set the object's type to be
double and assign the double value to the object's internal
representation doubleValue member. Tcl_SetDoubleObj
invalidates any old string representation and, if the object
is not already a double object, frees any old internal
representation.
Tcl_GetDoubleFromObj attempts to return a double value from
the Tcl object objPtr. If the object is not already a
double object, it will attempt to convert it to one. If an
error occurs during conversion, it returns TCL_ERROR and
leaves an error message in the interpreter's result object
unless interp is NULL. Otherwise, it returns TCL_OK and
stores the double value in the address given by doublePtr.
If the object is not already a double object, the conversion
will free any old internal representation.
SEE ALSO
Tcl_NewObj, Tcl_DecrRefCount, Tcl_IncrRefCount,
Tcl_GetObjResult
KEYWORDS
double, double object, double type, internal representation,
object, object type, string representation
Page 2 (printed 2/19/99)
