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Excerpt -- extraxt text from other files

In the Source File
In the Main File
Customization Via Buffer Local Variables
Types of excerpts
Known Problems
Version history


Extraxt text from other files and insert it in a main file. This is done using the following commands:

A general command for inserting excerpts. Use TAB-completion to see which excerpts are available in a certain file. (See also the variable `excerpt-sources'.)
Insert an excerpt from a file.
Insert a prefixed file excerpt.
Insert a source mark in the source file. The user will be asked to enter a category name.
Insert a source mark in the source file. The user will be asked to enter a category name and an ID.
`excerpt-insert-pseudo', `excerpt-insert-pseudo-with-prefix'
Insert a pseudo excerpt (a function or a variable) -- search for ":name excerpt-commands" in the source code for an example.

Installation: Put (require 'excerpt) (excerpt-install) into your startup/user init file.

In the Source File

In the source file these text portions are marked as

	<format-string NAME><comment-string>(<start-string> ID)
	text to be reported
	<comment-string>(<end-string> ID)

In elisp-mode this would be:

	<format-string NAME><comment-string>(<start-string> ID)
	text to be reported
	<comment-string>(<end-string> ID)

NAME ... a string -- may not contain ")"

FORMAT-STRING is mode sensitive but can be changed via buffer local variables. It is possible to use tags like LaTeX' \index.

START-STRING and END-STRING are global but can be changed via buffer local variables.

In the Main File

In the main file text to be reported is marked as

	<prefix><comment-string>(:excerpt NAME [:id ID])
	<prefix><comment-string>(:excerpt-source FILE-NAME)
	<prefix>[excerpted text]
	<prefix><comment-string>(:excerpt-end [ID])

This text is inserted with one `excerpt-insert' commands and automatically updated when setting the buffer/file-local variable `excerpt-update-flag' to t or when calling one of the `excerpt--update' commands -- preferably via the pop-up menu.

A local keymap covers the excerpt. Pressing Enter jumps to the source file; Space updates the excerpt if `excerpt-bind-space-to-update-flag' is non-nil; pressing Mouse-2 (or rather `excerpt-mouse-button') opens a pop-up menu.

If no ID is given, all occurances of category NAME are being excerpted. (Hm. To be honest, I'm not sure if this is true, if I planned to implement such a feature, and if I've already done so.)

The whole excerpt will be prefixed with the first line's PREFIX. This is a convenient way for inserting excerpts as comments.

The file/buffer local variable `excerpt-sources' defines where sources are normally located. The default file for `excerpt-insert' is either built on the value of this variable or the current buffer's file name.


Using regular expressions for finding excerpt sources and excerpt targets is of course a fragile solution. There are many ways to confuse excerpt.el. Here are some tips.

Headless Excerpts

Headless excerpt won't be visible as excerpts when the properties file is missing. Once the data of the properties file gets out of sync with the text, it's pretty hard to restore a headless excerpt properly. You can force the use of file-local variables by modifying `excerpt-use-file-local-variable', though.

Copy and Paste

When copying an excerpt, the overlays/extents are only maintained if the whole excerpt was selected. This is escpecially important with headless excerpts.


For hiding excerpt marks to the compiler, text formatter, preprocessor, or whatsoever, these marks are enclosed with COMMENT-START and COMMENT-END. This means of course that these variables have to be defined somewhere. Normally this is done by the major mode. If this is not the case, you could use file local variables or you could use some project management package that sets these variables for files in a certain directory.

Customization Via Buffer Local Variables

The following variables overwrite global settings if defined as local variables:

`excerpt-start-format-string', `excerpt-end-format-string'
Define source start and end marks.
`excerpt-start-string', `excerpt-end-string'
These variables are created by excerpt.el and define the excerpt start and end marks.
Either a file name or a directory name where excerpt sources are located.
If non-nil, update all excerpts after opening.

For setting these variables for all files in a specific directory, use some project management package. (You could also use CompEmacsFilesets, defining some custom :open function.)

Types of excerpts

At the moment there are two "types" of excerpts:

Insert marked excerpts.
Insert the whole file. When running the command `excerpt-insert', a pseudo excerpt with the name *FILE* is generated.

In addition, there are two pseudo excerpts, which can be inserted with the `excerpt-insert-pseudo' command: *FUNCTION* and *VARIABLE*. Evaluation and formatting of pseudo excerpts' sources is defined by three user options/variables: excerpt-allow-eval-functions, excerpt-allow-eval-variables, excerpt-pseudo-excerpt-list. Evaluation of functions is of course unsafe.

Known Problems


Requirements: tellib, file properties

v 0.3.1: excerpt.el.gz

All elisp files on this site: tellib.tar.gz

Version history

Change log

pseudo-excerpts (functions, variables), headless excerpts (excerpts with no textual markers)
non-intrusive source marks
initial release (experimental, tested with XEmacs 21.4.8)

(c) 2003 Thomas Link (last updated Aug 30 2003) home top