textutil::adjust(3Text and string utilities, macro procetextutil::adjust(3tcl)
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NAME
textutil::adjust - Procedures to adjust, indent, and undent paragraphs
SYNOPSIS
package require Tcl 8.2
package require textutil::adjust ?0.7.3?
::textutil::adjust::adjust string ?option value...?
::textutil::adjust::readPatterns filename
::textutil::adjust::listPredefined
::textutil::adjust::getPredefined filename
::textutil::adjust::indent string prefix ?skip?
::textutil::adjust::undent string
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DESCRIPTION
The package textutil::adjust provides commands that manipulate strings
or texts (a.k.a. long strings or string with embedded newlines or para-
graphs), adjusting, or indenting them.
The complete set of procedures is described below.
::textutil::adjust::adjust string ?option value...?
Do a justification on the string according to the options. The
string is taken as one big paragraph, ignoring any newlines.
Then the line is formatted according to the options used, and
the command returns a new string with enough lines to contain
all the printable chars in the input string. A line is a set of
characters between the beginning of the string and a newline, or
between 2 newlines, or between a newline and the end of the
string. If the input string is small enough, the returned string
won't contain any newlines.
Together with ::textutil::adjust::indent it is possible to cre-
ate properly wrapped paragraphs with arbitrary indentations.
By default, any occurrence of space or tabulation characters are
replaced by a single space so that each word in a line is sepa-
rated from the next one by exactly one space character, and this
forms a real line. Each real line is placed in a logical line,
which has exactly a given length (see the option -length below).
The real line may be shorter. Again by default, trailing spaces
are ignored before returning the string (see the option -full
below).
The following options may be used after the string parameter,
and change the way the command places a real line in a logical
line.
-full boolean
If set to false (default), trailing space characters are
deleted before returning the string. If set to true, any
trailing space characters are left in the string.
-hyphenate boolean
If set to false (default), no hyphenation will be done.
If set to true, the command will try to hyphenate the
last word of a line. Note: Hyphenation patterns must be
loaded prior, using the command ::textutil::adjust::read-
Patterns.
-justify center|left|plain|right
Sets the justification of the returned string to either
left (default), center, plain or right. The justification
means that any line in the returned string but the last
one is build according to the value. If the justifica-
tion is set to plain and the number of printable chars in
the last line is less than 90% of the length of a line
(see the option -length), then this line is justified
with the left value, avoiding the expansion of this line
when it is too small. The meaning of each value is:
center The real line is centered in the logical line. If
needed, a set of space characters are added at the
beginning (half of the needed set) and at the end
(half of the needed set) of the line if required
(see the option -full).
left The real line is set on the left of the logical
line. It means that there are no space chars at
the beginning of this line. If required, all
needed space chars are added at the end of the
line (see the option -full).
plain The real line is exactly set in the logical line.
It means that there are no leading or trailing
space chars. All the needed space chars are added
in the real line, between 2 (or more) words.
right The real line is set on the right of the logical
line. It means that there are no space chars at
the end of this line, and there may be some space
chars at the beginning, despite of the -full op-
tion.
-length integer
Set the length of the logical line in the string to inte-
ger. integer must be a positive integer value. Defaults
to 72.
-strictlength boolean
If set to false (default), a line can exceed the speci-
fied -length if a single word is longer than -length. If
set to true, words that are longer than -length are split
so that no line exceeds the specified -length.
::textutil::adjust::readPatterns filename
Loads the internal storage for hyphenation patterns with the
contents of the file filename. This has to be done prior to
calling command ::textutil::adjust::adjust with "-hyphenate
true", or the hyphenation process will not work correctly.
The package comes with a number of predefined pattern files, and
the command ::textutil::adjust::listPredefined can be used to
find out their names.
::textutil::adjust::listPredefined
This command returns a list containing the names of the hyphena-
tion files coming with this package.
::textutil::adjust::getPredefined filename
Use this command to query the package for the full path name of
the hyphenation file filename coming with the package. Only the
filenames found in the list returned by ::textutil::ad-
just::listPredefined are legal arguments for this command.
::textutil::adjust::indent string prefix ?skip?
Each line in the string is indented by adding the string prefix
at its beginning. The modified string is returned as the result
of the command.
If skip is specified the first skip lines are left untouched.
The default for skip is 0, causing the modification of all
lines. Negative values for skip are treated like 0. In other
words, skip > 0 creates a hanging indentation.
Together with ::textutil::adjust::adjust it is possible to cre-
ate properly wrapped paragraphs with arbitrary indentations.
::textutil::adjust::undent string
The command computes the common prefix for all lines in string
consisting solely out of whitespace, removes this from each line
and returns the modified string.
Lines containing only whitespace are always reduced to com-
pletely empty lines. They and empty lines are also ignored when
computing the prefix to remove.
Together with ::textutil::adjust::adjust it is possible to cre-
ate properly wrapped paragraphs with arbitrary indentations.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category textutil
of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please
also report any ideas for enhancements you may have for either package
and/or documentation.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
SEE ALSO
regexp(3tcl), split(3tcl), string(3tcl)
KEYWORDS
TeX, adjusting, formatting, hyphenation, indenting, justification,
paragraph, string, undenting
CATEGORY
Text processing
tcllib 0.7.3 textutil::adjust(3tcl)