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Tcl_DoubleObj(3tcl) Tcl Library Procedures Tcl_DoubleObj(3tcl) 





NAME


Tcl_NewDoubleObj, Tcl_SetDoubleObj, Tcl_GetDoubleFromObj -
    manipulate Tcl values 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
      value.

  
Tcl_Obj *objPtr (in/out)

  
For Tcl_SetDoubleObj, this points to the value in which to store a
      double value. For Tcl_GetDoubleFromObj, this refers to the value
      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.
    
    

    

  








DESCRIPTION


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


Tcl_NewDoubleObj creates and returns a new Tcl value
    initialized to the double value doubleValue. The returned Tcl value
    is unshared.


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


Tcl_GetDoubleFromObj attempts to retrieve a double value
    from the Tcl value 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 value, double type, internal representation, value,
    value type, string representation







  

    8.0
    Tcl