critcl::literals(n) C Runtime In Tcl (CriTcl) critcl::literals(n)______________________________________________________________________________NAME
critcl::literals - CriTcl Utilities: Constant string pools
SYNOPSIS
package require Tcl 8.4
package require critcl ?3.1.11?
package require critcl::literals ?1.1?
::critcl::literals::def name definition
______________________________________________________________________________DESCRIPTION
Welcome to the C Runtime In Tcl, CriTcl for short, a system to build C
extension packages for Tcl on the fly, from C code embedded within Tcl
scripts, for all who wish to make their code go faster.
This document is the reference manpage for the critcl::literals pack‐
age. This package provides convenience commands for advanced function‐
ality built on top of both critcl core and package critcl::iassoc.
Many packages will have a fixed set of string constants occuring in one
or places. Most of them will be coded to create a new string Tcl_Obj*
from a C char* every time the constant is needed, as this is easy to
to, despite the inherent waste of memory.
This package was written to make declaration and management of string
pools which do not waste memory as easy as the wasteful solution, hid‐
ing all attendant complexity from the user.
Its intended audience are mainly developers wishing to write Tcl pack‐
ages with embedded C code.
This package resides in the Core Package Layer of CriTcl.
+----------------+
|Applications |
| critcl |
| critcl::app |
+----------------+
*================*
|Core Packages |
| critcl |
| critcl::util |
*================*
+----------------+
|Support Packages|
| stubs::* |
| md5, platform |
| ... |
+----------------+
API
::critcl::literals::def name definition
This command defines a C function with the given name which pro‐
vides access to a pool of constant strings with a Tcl inter‐
preter.
The definition dictionary provides the mapping from the C-level
symbolic names to the string themselves.
The new function has two parameters, a Tcl_Interp* pointer
refering to the interpreter holding the string pool, and a code
of type "name_names" (see below), the symbolic name of the lit‐
eral to return. Tcl result of the function is a Tcl_Obj* pointer
to the requested string constant.
The underlying string pool is automatically initialized on first
access, and finalized on interpreter destruction.
The package generates multiple things (declarations and defini‐
tions) with names derived from name, which has to be a proper C
identifier.
name The function providing access to the string pool. Its
signature is
Tcl_Obj* name (Tcl_Interp* interp, name_names literal);
name_names
A C enumeration type containing the symbolic names of the
strings provided by the pool.
name.h A header file containing the declarations for the acces‐
sor function and enumeration type, for use by other parts
of the system, if necessary.
The generated file is stored in a place where it will not
interfere with the overall system outside of the package,
yet also be available for easy inclusion by package files
(csources).
name New in version 1.1: At the level of critcl itself the
command registers a new result-type for critcl::cproc,
which takes an integer result from the function and con‐
verts it to the equivalent string in the pool for the
script.
EXAMPLE
The example shown below is the specification of the string pool pulled
from the draft work on a Tcl binding to Linux's inotify APIs.
package require Tcl 8.5
package require critcl 3.1.11
critcl::buildrequirement {
package require critcl::literals
}
critcl::literals::def tcl_inotify_strings {
w_create"create"
w_directory"directory"
w_events"events"
w_file"file"
w_handler"handler"
w_remove"remove"
}
# Declarations: tcl_inotify_strings.h
# Type: tcl_inotify_strings_names
# Accessor: Tcl_Obj* tcl_inotify_strings (Tcl_Interp* interp,
# tcl_inotify_strings_names literal);
# ResultType: tcl_inotify_strings
AUTHORS
Andreas Kupries
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such at
https://github.com/andreas-kupries/critcl. Please also report any
ideas for enhancements you may have for either package and/or documen‐
tation.
KEYWORDS
C code, Embedded C Code, Tcl Interp Association, code generator, com‐
pile & run, compiler, dynamic code generation, dynamic compilation,
generate package, linker, literal pool, on demand compilation, on-the-
fly compilation, singleton, string pool
CATEGORY
Glueing/Embedded C code
COPYRIGHT
Copyright (c) 2011-2015 Andreas Kupries
doc 1.1 critcl::literals(n)
