Tcl_BooleanObj(3) Tcl (8.0) Tcl_BooleanObj(3)
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NAME
Tcl_NewBooleanObj, Tcl_SetBooleanObj, Tcl_GetBooleanFromObj
- manipulate Tcl objects as boolean values
SYNOPSIS
#include <tcl.h>
Tcl_Obj *
Tcl_NewBooleanObj(boolValue)
Tcl_SetBooleanObj(objPtr, boolValue)
int
Tcl_GetBooleanFromObj(interp, objPtr, boolPtr)
ARGUMENTS
int boolValue (in) Integer value used to
initialize or set a boolean
object. If the integer is
nonzero, the boolean object
is set to 1; otherwise the
boolean object is set to 0.
Tcl_Obj *objPtr (in/out) For Tcl_SetBooleanObj, this
points to the object to be
converted to boolean type.
For Tcl_GetBooleanFromObj,
this refers to the object
from which to get a boolean
value; if objPtr does not
already point to a boolean
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.
int *boolPtr (out) Points to place where
Tcl_GetBooleanFromObj
stores the boolean value (0
or 1) obtained from objPtr.
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DESCRIPTION
These procedures are used to create, modify, and read
boolean Tcl objects from C code. Tcl_NewBooleanObj and
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Tcl_BooleanObj(3) Tcl (8.0) Tcl_BooleanObj(3)
Tcl_SetBooleanObj will create a new object of boolean type
or modify an existing object to have boolean type. Both of
these procedures set the object to have the boolean value (0
or 1) specified by boolValue; if boolValue is nonzero, the
object is set to 1, otherwise to 0. Tcl_NewBooleanObj
returns a pointer to a newly created object with reference
count zero. Both procedures set the object's type to be
boolean and assign the boolean value to the object's
internal representation longValue member. Tcl_SetBooleanObj
invalidates any old string representation and, if the object
is not already a boolean object, frees any old internal
representation.
Tcl_GetBooleanFromObj attempts to return a boolean value
from the Tcl object objPtr. If the object is not already a
boolean 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, Tcl_GetBooleanFromObj
returns TCL_OK and stores the boolean value in the address
given by boolPtr. If the object is not already a boolean
object, the conversion will free any old internal
representation.
SEE ALSO
Tcl_NewObj, Tcl_DecrRefCount, Tcl_IncrRefCount,
Tcl_GetObjResult
KEYWORDS
boolean, boolean object, boolean type, internal
representation, object, object type, string representation
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