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Tcl_NewDoubleObj(3tcl)




Tcl_DoubleObj(3)     Tcl Library Procedures      Tcl_DoubleObj(3)

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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 Tcl object.

     Tcl_Obj *objPtr (in/out)             For   Tcl_SetDoubleObj,
                                          this   points   to  the
                                          object  in   which   to
                                          store  a  double value.
                                          For
                                          Tcl_GetDoubleFromObj,
                                          this  refers   to   the
                                          object  from  which  to
                                          retrieve    a    double
                                          value.

     Tcl_Interp *interp (in/out)          When non-NULL, an error
                                          message  is  left  here
                                          when    double    value
                                          retrieval fails.

     double *doublePtr (out)              Points  to   place   to
                                          store  the double value
                                          obtained from objPtr.
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DESCRIPTION

     These procedures are used to create, modify,  and  read  Tcl
     objects that hold double-precision floating-point values.

     Tcl_NewDoubleObj creates and returns a new Tcl  object  ini-
     tialized  to the double value doubleValue.  The returned Tcl
     object is unshared.

Tcl                     Last change: 8.0                        1

Tcl_DoubleObj(3)     Tcl Library Procedures      Tcl_DoubleObj(3)

     Tcl_SetDoubleObj sets the value of an  existing  Tcl  object
     pointed  to  by objPtr to the double value doubleValue.  The
     objPtr argument must point to an unshared Tcl  object.   Any
     attempt  to  set  the  value of a shared Tcl object violates
     Tcl's copy-on-write policy.  Any existing string representa-
     tion  or  internal representation in the unshared Tcl object
     will be freed as a consequence of setting the new value.

     Tcl_GetDoubleFromObj attempts to  retrieve  a  double  value
     from  the  Tcl object objPtr.  If the attempt succeeds, then
     TCL_OK is returned, and the double value is written  to  the
     storage pointed to by doublePtr.  If the attempt fails, then
     TCL_ERROR is returned, and if interp is non-NULL,  an  error
     message is left in interp.  The Tcl_ObjType of objPtr may be
     changed to make  subsequent  calls  to  Tcl_GetDoubleFromObj
     more efficient.


SEE ALSO

     Tcl_NewObj,       Tcl_DecrRefCount,        Tcl_IncrRefCount,
     Tcl_GetObjResult


KEYWORDS

     double, double object, double type, internal representation,
     object, object type, string representation

Tcl                     Last change: 8.0                        2


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