Tcl_BooleanObj(3)					      Tcl Library Procedures						 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_GetBooleanFro-
					mObj,  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 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  bool-
       ean  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 inter-
       preter'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.  Objects having
       a string representation equal to any of 0, false, no, or off have a boolean value 0; if the string representation is any of 1,  true,  yes,
       or on the boolean value is 1.  Any of these string values may be abbreviated, and upper-case spellings are also acceptable.

SEE ALSO

       Tcl_NewObj, Tcl_DecrRefCount, Tcl_IncrRefCount, Tcl_GetObjResult

KEYWORDS

       boolean, boolean object, boolean type, internal representation, object, object type, string representation

Tcl									8.0							 Tcl_BooleanObj(3)