Tcl_Namespace(3) Tcl Library Procedures Tcl_Namespace(3)

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NAME

Tcl_AppendExportList, Tcl_CreateNamespace, Tcl_DeleteNamespace,
Tcl_Export, Tcl_FindCommand, Tcl_FindNamespace, Tcl_ForgetImport,
Tcl_GetCurrentNamespace, Tcl_GetGlobalNamespace,
Tcl_GetNamespaceUnknownHandler, Tcl_Import,
Tcl_SetNamespaceUnknownHandler - manipulate namespaces

SYNOPSIS

#include <tcl.h>

Tcl_Namespace *
Tcl_CreateNamespace(interp, name, clientData, deleteProc)

Tcl_DeleteNamespace(nsPtr)

int
Tcl_AppendExportList(interp, nsPtr, objPtr)

int
Tcl_Export(interp, nsPtr, pattern, resetListFirst)

int
Tcl_Import(interp, nsPtr, pattern, allowOverwrite)

int
Tcl_ForgetImport(interp, nsPtr, pattern)

Tcl_Namespace *
Tcl_GetCurrentNamespace(interp)

Tcl_Namespace *
Tcl_GetGlobalNamespace(interp)

Tcl_Namespace *
Tcl_FindNamespace(interp, name, contextNsPtr, flags)

Tcl_Command
Tcl_FindCommand(interp, name, contextNsPtr, flags)

Tcl_Obj *
Tcl_GetNamespaceUnknownHandler(interp, nsPtr)

int
Tcl_SetNamespaceUnknownHandler(interp, nsPtr, handlerPtr)

ARGUMENTS

Tcl_Interp *interp (in/out) The interpreter
in which the
namespace exists
and where name
lookups are
performed. Also
where error
result messages
are written.

const char *name (in) The name of the
namespace or
command to be
created or
accessed.

ClientData clientData (in) A context
pointer by the
creator of the
namespace. Not
interpreted by
Tcl at all.

Tcl_NamespaceDeleteProc *deleteProc (in) A pointer to
function to call
when the
namespace is
deleted, or NULL
if no such
callback is to
be performed.

Tcl_Namespace *nsPtr (in) The namespace to
be manipulated,
or NULL (for
other than
Tcl_DeleteNamespace)
to manipulate
the current
namespace.

Tcl_Obj *objPtr (out) A reference to
an unshared
value to which
the function
output will be
written.

const char *pattern (in) The glob-style
pattern (see
Tcl_StringMatch)
that describes
the commands to
be imported or
exported.

int resetListFirst (in) Whether the list
of export
patterns should
be reset before
adding the
current pattern
to it.

int allowOverwrite (in) Whether new
commands created
by this import
action can
overwrite
existing
commands.

Tcl_Namespace *contextNsPtr (in) The location in
the namespace
hierarchy where
the search for a
namespace or
command should
be conducted
relative to when
the search term
is not rooted at
the global
namespace. NULL
indicates the
current
namespace.

int flags (in) OR-ed
combination of
bits controlling
how the search
is to be
performed. The
following flags
are supported:
TCL_GLOBAL_ONLY
(indicates that
the search is
always to be
conducted
relative to the
global
namespace),
TCL_NAMESPACE_ONLY
(just for
Tcl_FindCommand;
indicates that
the search is
always to be
conducted
relative to the
context
namespace), and
TCL_LEAVE_ERR_MSG
(indicates that
an error message
should be left
in the
interpreter if
the search
fails.)

Tcl_Obj *handlerPtr (in) A script
fragment to be
installed as the
unknown command
handler for the
namespace, or
NULL to reset
the handler to
its default.
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DESCRIPTION

Namespaces are hierarchic naming contexts that can contain commands
and variables. They also maintain a list of patterns that describes
what commands are exported, and can import commands that have been
exported by other namespaces. Namespaces can also be manipulated
through the Tcl command namespace.

The Tcl_Namespace structure encapsulates a namespace, and is
guaranteed to have the following fields in it: name (the local name
of the namespace, with no namespace separator characters in it, with
empty denoting the global namespace), fullName (the fully specified
name of the namespace), clientData, deleteProc (the values specified
in the call to Tcl_CreateNamespace), and parentPtr (a pointer to the
containing namespace, or NULL for the global namespace.)

Tcl_CreateNamespace creates a new namespace. The deleteProc will
have the following type signature:

typedef void Tcl_NamespaceDeleteProc(
ClientData clientData);

Tcl_DeleteNamespace deletes a namespace, calling the deleteProc
defined for the namespace (if any).

Tcl_AppendExportList retrieves the export patterns for a namespace
given namespace and appends them (as list items) to objPtr.

Tcl_Export sets and appends to the export patterns for a namespace.
Patterns are appended unless the resetListFirst flag is true.

Tcl_Import imports commands matching a pattern into a namespace.
Note that the pattern must include the name of the namespace to
import from. This function returns TCL_ERROR if an attempt to import
a command over an existing command is made, unless the allowOverwrite
flag has been set.

Tcl_ForgetImport removes imports matching a pattern.

Tcl_GetCurrentNamespace returns the current namespace for an
interpreter.

Tcl_GetGlobalNamespace returns the global namespace for an
interpreter.

Tcl_FindNamespace searches for a namespace named name within the
context of the namespace contextNsPtr. If the namespace cannot be
found, NULL is returned.

Tcl_FindCommand searches for a command named name within the context
of the namespace contextNsPtr. If the command cannot be found, NULL
is returned.

Tcl_GetNamespaceUnknownHandler returns the unknown command handler
for the namespace, or NULL if none is set.

Tcl_SetNamespaceUnknownHandler sets the unknown command handler for
the namespace. If handlerPtr is NULL, then the handler is reset to
its default.

SEE ALSO

Tcl_CreateCommand(3), Tcl_ListObjAppendList(3), Tcl_SetVar(3)

KEYWORDS

namespace, command

Tcl 8.5 Tcl_Namespace(3)