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Tcl_IntObj(3) Tcl Library Procedures Tcl_IntObj(3)
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NAME
Tcl_NewIntObj, Tcl_NewLongObj, Tcl_NewWideIntObj, Tcl_SetIntObj,
Tcl_SetLongObj, Tcl_SetWideIntObj, Tcl_GetIntFromObj,
Tcl_GetLongFromObj, Tcl_GetWideIntFromObj, Tcl_NewBignumObj,
Tcl_SetBignumObj, Tcl_GetBignumFromObj, Tcl_TakeBignumFromObj -
manipulate Tcl values as integers
SYNOPSIS
#include <tcl.h>
Tcl_Obj *
Tcl_NewIntObj(intValue)
Tcl_Obj *
Tcl_NewLongObj(longValue)
Tcl_Obj *
Tcl_NewWideIntObj(wideValue)
Tcl_SetIntObj(objPtr, intValue)
Tcl_SetLongObj(objPtr, longValue)
Tcl_SetWideIntObj(objPtr, wideValue)
int
Tcl_GetIntFromObj(interp, objPtr, intPtr)
int
Tcl_GetLongFromObj(interp, objPtr, longPtr)
int
Tcl_GetWideIntFromObj(interp, objPtr, widePtr)
#include <tclTomMath.h>
Tcl_Obj *
Tcl_NewBignumObj(bigValue)
Tcl_SetBignumObj(objPtr, bigValue)
int
Tcl_GetBignumFromObj(interp, objPtr, bigValue)
int
Tcl_TakeBignumFromObj(interp, objPtr, bigValue)
int
Tcl_InitBignumFromDouble(interp, doubleValue, bigValue)
ARGUMENTS
int intValue (in) Integer value used to initialize
or set a Tcl value.
long longValue (in) Long integer value used to
initialize or set a Tcl value.
Tcl_WideInt wideValue (in) Wide integer value used to
initialize or set a Tcl value.
Tcl_Obj *objPtr (in/out) For Tcl_SetIntObj,
Tcl_SetLongObj,
Tcl_SetWideIntObj, and
Tcl_SetBignumObj, this points to
the value in which to store an
integral value. For
Tcl_GetIntFromObj,
Tcl_GetLongFromObj,
Tcl_GetWideIntFromObj,
Tcl_GetBignumFromObj, and
Tcl_TakeBignumFromObj, this
refers to the value from which to
retrieve an integral value.
Tcl_Interp *interp (in/out) When non-NULL, an error message
is left here when integral value
retrieval fails.
int *intPtr (out) Points to place to store the
integer value retrieved from
objPtr.
long *longPtr (out) Points to place to store the long
integer value retrieved from
objPtr.
Tcl_WideInt *widePtr (out) Points to place to store the wide
integer value retrieved from
objPtr.
mp_int *bigValue (in/out) Points to a multi-precision
integer structure declared by the
LibTomMath library.
double doubleValue (in) Double value from which the
integer part is determined and
used to initialize a multi-
precision integer value.
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DESCRIPTION
These procedures are used to create, modify, and read Tcl values that
hold integral values.
The different routines exist to accommodate different integral types in
C with which values might be exchanged. The C integral types for which
Tcl provides value exchange routines are int, long int, Tcl_WideInt,
and mp_int. The int and long int types are provided by the C language
standard. The Tcl_WideInt type is a typedef defined to be whatever
signed integral type covers at least the 64-bit integer range
(-9223372036854775808 to 9223372036854775807). Depending on the
platform and the C compiler, the actual type might be long int, long
long int, __int64, or something else. The mp_int type is a multiple-
precision integer type defined by the LibTomMath multiple-precision
integer library.
The Tcl_NewIntObj, Tcl_NewLongObj, Tcl_NewWideIntObj, and
Tcl_NewBignumObj routines each create and return a new Tcl value
initialized to the integral value of the argument. The returned Tcl
value is unshared.
The Tcl_SetIntObj, Tcl_SetLongObj, Tcl_SetWideIntObj, and
Tcl_SetBignumObj routines each set the value of an existing Tcl value
pointed to by objPtr to the integral value provided by the other
argument. 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.
The Tcl_GetIntFromObj, Tcl_GetLongFromObj, Tcl_GetWideIntFromObj,
Tcl_GetBignumFromObj, and Tcl_TakeBignumFromObj routines attempt to
retrieve an integral value of the appropriate type from the Tcl value
objPtr. If the attempt succeeds, then TCL_OK is returned, and the
value is written to the storage provided by the caller. The attempt
might fail if objPtr does not hold an integral value, or if the value
exceeds the range of the target type. 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 the same routine more efficient. Unlike the other
functions, Tcl_TakeBignumFromObj may set the content of the Tcl value
objPtr to an empty string in the process of retrieving the multiple-
precision integer value.
The choice between Tcl_GetBignumFromObj and Tcl_TakeBignumFromObj is
governed by how the caller will continue to use objPtr. If after the
mp_int value is retrieved from objPtr, the caller will make no more use
of objPtr, then using Tcl_TakeBignumFromObj permits Tcl to detect when
an unshared objPtr permits the value to be moved instead of copied,
which should be more efficient. If anything later in the caller
requires objPtr to continue to hold the same value, then
Tcl_GetBignumFromObj must be chosen.
The Tcl_InitBignumFromDouble routine is a utility procedure that
extracts the integer part of doubleValue and stores that integer value
in the mp_int value bigValue.
SEE ALSO
Tcl_NewObj, Tcl_DecrRefCount, Tcl_IncrRefCount, Tcl_GetObjResult
KEYWORDS
integer, integer value, integer type, internal representation, value,
value type, string representation
Tcl 8.5 Tcl_IntObj(3)