annotate modules/README @ 5566:4654c01af32b

Improve the implementation, documentation of #'labels, #'flet. lisp/ChangeLog addition: 2011-09-07 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el: * bytecomp.el (for-effect): Move this earlier in the file, it's referenced in byte-compile-initial-macro-environment. * bytecomp.el (byte-compile-initial-macro-environment): In the byte-compile-macro-environment definition for #'labels, put off the compiling the lambda bodies until the point where the rest of the form is being compiled, allowing the lambda bodies to access appropriate values for byte-compile-bound-variables, and reducing excessive warning about free variables. Add a byte-compile-macro-environment definition for #'flet. This modifies byte-compile-function-environment appropriately, and warns about bindings of functions that have macro definitions in the current environment, about functions that have byte codes, and about functions that have byte-compile methods (which may not do what the user wants at runtime). * bytecomp.el (byte-compile-funcall): If FUNCTION is constant, call #'byte-compile-callargs-warn if that's appropriate, giving warnings about problems with calling functions bound with #'labels. * cl-macs.el: * cl-macs.el (flet): Mention the main difference from Common Lisp, that the bindings are dynamic, not lexical. Counsel the use of #'labels, not #'flet, for this and other reasons. Explain the limited single use case for #'flet. Cross-reference to bytecomp.el in a comment. * cl-macs.el (labels): Go into detail on which functions may be called from where. Explain how to access the function definition of a label within FORM. Add a comment cross-referencing to bytecomp.el. man/ChangeLog addition: 2011-09-07 Aidan Kehoe <kehoea@parhasard.net> * cl.texi (Function Bindings): Move #'labels first, describe it in more detail, explaining that it is to be preferred over #'flet, and explaining why. Explain that dynamic bindings with #'flet will also not work when functions are accessed through their bytecodes.
author Aidan Kehoe <kehoea@parhasard.net>
date Wed, 07 Sep 2011 16:26:45 +0100
parents da1365dd3f07
children
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1 This file is part of XEmacs.
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2
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3 XEmacs is free software: you can redistribute it and/or modify it
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4 under the terms of the GNU General Public License as published by the
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5 Free Software Foundation, either version 3 of the License, or (at your
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6 option) any later version.
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8 XEmacs is distributed in the hope that it will be useful, but WITHOUT
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9 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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10 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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11 for more details.
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13 You should have received a copy of the GNU General Public License
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14 along with XEmacs. If not, see <http://www.gnu.org/licenses/>.
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17 This directory contains a number of XEmacs dynamic modules. These
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18 modules can be loaded directly with the command 'M-x load-module'.
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19 However, the preferred method of loading a module is to issue a
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20 "(require 'module-name)" command to the Lisp interpreter. This will
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21 store information so that a later "(unload-feature 'module-name)" can
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22 succeed.
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24 To compile one of these modules, simply enter the desired directory,
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25 type 'configure', and then 'make'. If you are building the module for
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26 an installed XEmacs, then 'make install' will place the module in the
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27 appropriate directory for XEmacs to find it later (assuming you have
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28 permission to write to that directory). A subsequent 'load-module' or
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29 'require' will then load the module, as described above.
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31 Each of these demonstrates different features and limitations of the
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32 XEmacs module loading technology. For a complete discussion on XEmacs
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33 dynamic modules, please consult the XEmacs Module Writers Guide, which
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34 can be found in the ../info directory.
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36 For those wanting to get started with module writing, please see the
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37 'sample' directory. It contains two subdirectories: internal and
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38 external. The 'internal' subdirectory contains the framework needed to
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39 migrate some core piece of XEmacs functionality into code that can
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40 either be compiled into the core or built as a separate module. The
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41 'external' subdirectory contains the somewhat simpler framework needed
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42 to build a module separately from XEmacs. These should be considered
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43 starting places for module writing.