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*********************
* par.doc *
* for Par 1.50 *
* Copyright 1996 by *
* Adam M. Costello *
*********************
Par 1.50 is a package containing:
+ This doc file.
+ A man page based on this doc file.
+ The ANSI C source for the filter "par".
Contents
Contents
File List
Rights and Responsibilities
Compilation
Synopsis
Description
*Quick Start
Terminology
Options
Environment
Details
Diagnostics
Examples
Limitations
Apologies
Bugs
File List
The Par 1.50 package is always distributed with at least the
following files:
buffer.c
buffer.h
charset.c
charset.h
errmsg.c
errmsg.h
par.1
par.c
par.doc
protoMakefile
reformat.c
reformat.h
releasenotes
Each file is a text file which identifies itself on the second line,
and identifies the version of Par to which it belongs on the third
line, so you can always tell which file is which, even if the files
have been renamed.
The file "par.1" is a man page for the filter par (not to be
confused with the package Par, which contains the source code for
par). "par.1" is based on this doc file, and conveys much (not
all) of the same information, but "par.doc" is the definitive
documentation for both par and Par.
Rights and Responsibilities
The files listed in the Files List section above are each Copyright
1996 by Adam M. Costello (henceforth "I", "me").
I grant everyone permission to use these files in any way, subject
to the following two restrictions:
1) No one may distribute any one of the files unless it is
accompanied by all of the other files.
2) No one (except me) may distribute a modified version of one of
the files unless it clearly identifies itself as a modified
version, and it is accompanied by the original version of the
file.
Regardless of whether modifications get distributed or not, I would
appreciate being sent copies in case I wish to incorporate them into
future versions of Par. See the Bugs section for my addresses.
All official versions of Par will have version numbers that fit the
pattern "<digits>.<digits>". Those who distribute modified files
should, as a courtesy, make sure to modify the version number (which
appears in many places--search for it) to something that doesn't
fit the pattern, to avoid confusion between official versions and
modified versions.
Though I have tried to make sure that Par is free of bugs, I make no
guarantees about its soundness. Therefore, I am not responsible for
any damage resulting from the use of these files.
Compilation
To compile par, you need an ANSI C compiler. Follow the
instructions in the comments in protoMakefile.
If your compiler generates any warnings that you think are
legitimate, please tell me about them (see the Bugs section).
Note that all variables in par are either constant or automatic
(or both), which means that par can be made reentrant (if your
compiler supports it). Given the right operating system, it should
be possible for several par processes to share the same code space
and the same data space (but not the same stack, of course) in
memory.
Synopsis
par [help] [version] [B<op><set>] [P<op><set>] [Q<op><set>]
[h[<hang>]] [p[<prefix>]] [r[<repeat>]] [s[<suffix>]] [T[<Tab>]]
[w[<width>]] [b[<body>]] [c[<cap>]] [d[<div>]] [E[<Err>]]
[e[<expel>]] [f[<fit>]] [g[<guess>]] [i[<invis>]] [j[<just>]]
[l[<last>]] [q[<quote>]] [R[<Report>]] [t[<touch>]]
Things enclosed in [square brackets] are optional. Things enclosed
in <angle brackets> are parameters.
Description
par is a filter which copies its input to its output, changing all
white characters (except newlines) to spaces, and reformatting
each paragraph. Paragraphs are separated by protected, blank, and
bodiless lines (see the Terminology section for definitions), and
optionally delimited by indentation (see the d option in the Options
section).
Each output paragraph is generated from the corresponding input
paragraph as follows:
1) An optional prefix and/or suffix is removed from each input
line.
2) The remainder is divided into words (separated by spaces).
3) The words are joined into lines to make an eye-pleasing
paragraph.
4) The prefixes and suffixes are reattached.
If there are suffixes, spaces are inserted before them so that they
all end in the same column.
Quick Start
par is necessarily complex. For those who wish to use it
immediately and understand it later, assign to the PARINIT
environment variable the following value:
rTbgqR B=.?_A_a Q=_s>|
The spaces, question mark, greater-than sign, and vertical bar will
probably have to be escaped or quoted to prevent your shell from
interpreting them.
The documentation, though precise, is unfortunately not well-written
for the end-user. Your best bet is probably to read quickly the
Description, Terminology, Options, and Environment sections, then
read carefully the Examples section, referring back to the Options
and Terminology sections as needed.
For the "power user", a full understanding of par will require
multiple readings of the Terminology, Options, Details, and Examples
sections.
Terminology
Miscellaneous terms:
charset syntax
A way of representing a set of characters as a string.
The set includes exactly those characters which appear in
the string, except that the underscore (_) is an escape
character. Whenever it appears, it must begin one of the
following escape sequences:
__ = an underscore
_s = a space
_b = a backslash (\)
_q = a single quote (')
_Q = a double quote (")
_A = all upper case letters
_a = all lower case letters
_0 = all decimal digits
_xhh = the character represented by the two hexadecimal
digits hh (which may be upper or lower case)
The NUL character must not appear in the string but it may
be included in the set with the _x00 sequence.
error
A condition which causes par to abort. See the Diagnostics
section.
IP Input paragraph.
OP Output paragraph.
parameter
A symbol which may take on unsigned integral values. There
are several parameters whose values affect the behavior of
par. Parameters can be assigned values using command line
options.
Types of characters:
alphanumeric character
An upper case letter, lower case letter, or decimal digit.
body character
A member of the set of characters defined by the PARBODY
environment variable (see the Environment section) and/or
the B option (see the Options section).
protective character
A member of the set of characters defined by the PARPROTECT
environment variable and/or the P option.
quote character
A member of the set of characters defined by the PARQUOTE
environment variable and/or the Q option.
terminal character
A period, question mark, exclamation point, or colon.
white character
A space, formfeed, newline, carriage return, tab, or
vertical tab.
Functions:
comprelen
Given a non-empty sequence <S> of lines, let <c> be their
longest common prefix. If the parameter <body> is 0, place
a divider just after the leading non-body characters in <c>
(at the beginning if there are none). If <body> is 1, place
the divider just after the last non-space non-body character
in <c> (at the beginning if there is none), then advance
the divider over any immediately following spaces. The
comprelen of <S> is the number of characters preceeding the
divider.
comsuflen
Given a non-empty sequence <S> of lines, let <p> be the
comprelen of <S>. Let <T> be the set of lines which results
from stripping the first <p> characters from each line in
<S>. Let <c> be the longest common suffix of the lines
in <T>. If <body> is 0, place a divider just before the
trailing non-body characters in <c> (at the end if there are
none), then advance the divider over all but the last of any
immediately following spaces. If <body> is 1, place the
divider just before the first non-space non-body character,
then back up the divider over one immediately preceeding
space if there is one. The comsuflen of <S> is the number
of characters following the divider.
fallback prelen (suflen)
The fallback prelen (suflen) of an IP is: the comprelen
(comsuflen) of the IP, if the IP contains at least two
lines; otherwise, the comprelen (comsuflen) of the block
containing the IP, if the block contains at least two
lines; otherwise, the length of the longer of the prefixes
(suffixes) of the bodiless lines just above and below the
block, if the segment containing the block has any bodiless
lines; otherwise, 0. (See below for the definitions of
block, segment, and bodiless line.)
augmented fallback prelen
Let <fp> be the fallback prelen of an IP. If the IP
contains more than one line, or if <quote> is 0, then
the augmented fallback prelen of the IP is simply <fp>.
Otherwise, it is <fp> plus the number of quote characters
immediately following the first <fp> characters of the line.
quoteprefix
The quoteprefix of a line is the longest string of quote
characters appearing at the beginning of the line, after
this string has been stripped of any trailing spaces.
Types of lines:
blank line
An empty line, or a line whose first character is not
protective and which contains only spaces.
protected line
An input line whose first character is protective.
bodiless line
A line which is order <k> bodiless for some <k>.
order <k> bodiless line
There is no such thing as an order 0 bodiless line. Suppose
<S> is a a contiguous subsequence of a segment (see below)
containing at least two lines, containing no order <k>-1
bodiless lines, bounded above and below by order <k>-1
bodiless lines and/or the beginning/end of the segment.
Let <p> and <s> be the comprelen and comsuflen of <S>.
Any member of <S> which, if stripped of its first <p> and
last <s> characters, would be blank (or, if the parameter
<repeat> is non-zero, would consist of the same character
repeated at least <repeat> times), is order <k> bodiless.
The first <p> characters of the bodiless line comprise its
prefix; the last <s> characters comprise its suffix. The
character which repeats in the middle is called its repeat
character. If the middle is empty, the space is taken to be
its repeat character.
vacant line
A bodiless line whose repeat character is the space.
superfluous line
Only blank and vacant lines may be superfluous. If
contiguous vacant lines lie at the beginning or end of
a segment, they are all superfluous. But if they lie
between two non-vacant lines within a segment, then all are
superfluous except one--the one which contains the fewest
non-spaces. In case of a tie, the first of the tied lines
is chosen. Similarly, if contiguous blank lines lie outside
of any segments at the beginning or end of the input, they
are all superfluous. But if they lie between two segments
and/or protected lines, then all are superfluous except the
first.
Groups of lines:
segment
A contiguous sequence of input lines containing no protected
or blank lines, bounded above and below by protected lines,
blank lines, and/or the beginning/end of the input.
block
A contiguous subsequence of a segment containing no bodiless
lines, bounded above and below by bodiless lines and/or the
beginning/end of the segment.
Types of words:
capitalized word
If the parameter <cap> is 0, a capitalized word is one which
contains at least one alphanumeric character, whose first
alphanumeric character is not a lower case letter. If <cap>
is 1, every word is considered a capitalized word. (See the
c option in the Options section.)
curious word
A word which contains a terminal character <c> such that
there are no alphanumeric characters in the word after <c>,
but there is at least one alphanumeric character in the word
before <c>.
Options
Any command line argument may begin with one minus sign (-) which
is ignored. Generally, more than one option may appear in a single
command line argument, but there are exceptions: The help, version,
B, P, and Q options must have whole arguments all to themselves.
help Causes all remaining arguments to be ignored. No input
is read. A usage message is printed on the output
briefly describing the options used by par.
version Causes all remaining arguments to be ignored. No input
is read. "par 1.50" is printed on the output. Of
course, this will change in future releases of Par.
B<op><set> <op> is a single character, either an equal sign (=),
a plus sign (+), or a minus sign (-), and <set> is a
string using charset syntax. If <op> is an equal sign,
the set of body characters is set to the character set
defined by <set>. If <op> is a plus/minus sign, the
characters in the set defined by <set> are added/removed
to/from the existing set of body characters defined by
the PARBODY environment variable and any previous B
options. It is okay to add characters that are already
in the set or to remove characters that are not in the
set.
P<op><set> Just like the B option, except that it applies to the
set of protective characters.
Q<op><set> Just like the B option, except that it applies to the
set of quote characters.
All remaining options are used to set values of parameters. Values
set by command line options hold for all paragraphs. Unset
parameters are given default values. Any parameters whose default
values depend on the IP (namely <prefix> and <suffix>), if left
unset, are recomputed separately for each paragraph.
The approximate role of each parameter is described here. See the
Details section for the rest of the story.
The first six parameters, <hang>, <prefix>, <repeat>, <suffix>,
<Tab>, and <width>, may be set to any unsigned decimal integer less
than 10000.
h[<hang>] Mainly affects the default values of <prefix> and
<suffix>. Defaults to 0. If the h option is given
without a number, the value 1 is inferred. (See also
the p and s options.)
p[<prefix>] The first <prefix> characters of each line of the OP
are copied from the first <prefix> characters of the
corresponding line of the IP. If there are more than
<hang>+1 lines in the IP, the default value is the
comprelen of all the lines in the IP except the first
<hang> of them. Otherwise, the default value is the
augmented fallback prelen of the IP. If the p option is
given without a number, <prefix> is unset, even if it
had been set earlier. (See also the h and q options.)
r[<repeat>] If <repeat> is non-zero, bodiless lines have the number
of instances of their repeat characters increased or
decreased until the length of the line is <width>.
The exact value of <repeat> affects the definition of
bodiless line. Defaults to 0. If the r option is given
without a number, the value 3 is inferred. (See also
the w option.)
s[<suffix>] The last <suffix> characters of each line of the OP
are copied from the last <suffix> characters of the
corresponding line of the IP. If there are more than
<hang>+1 lines in the IP, the default value is the
comsuflen of all the lines in the IP except the first
<hang> of them. Otherwise, the default value is the
fallback suflen of the IP. If the s option is given
without a number, <suffix> is unset, even if it had been
set earlier. (See also the h option.)
T[<Tab>] Tab characters in the input are expanded to spaces,
assuming tab stops every <Tab> columns. Must not be
0. Defaults to 1. If the T option is given without a
number, the value 8 is inferred.
w[<width>] No line in the OP may contain more than <width>
characters, not including the trailing newlines.
Defaults to 72. If the w option is given without a
number, the value 79 is inferred.
The remaining thirteen parameters, <body>, <cap>, <div>, <Err>,
<expel>, <fit>, <guess>, <invis>, <just>, <last>, <quote>, <Report>,
and <touch>, may be set to either 0 or 1. If the number is absent
in the option, the value 1 is inferred.
b[<body>] If <body> is 1, prefixes may not contain any trailing
body characters, and suffixes may not contain any
leading body characters. (Actually, the situation
is complicated by space characters. See comprelen
and comsuflen in the Terminology section.) If <body>
is 0, prefixes and suffixes may not contain any body
characters at all. Defaults to 0.
c[<cap>] If <cap> is 1, all words are considered capitalized.
This currently affects only the application of the g
option. Defaults to 0.
d[<div>] If <div> is 0, each block becomes an IP. If <div> is 1,
each block is subdivided into IPs as follows: Let <p>
be the comprelen of the block. Let a line's status be
1 if its (<p>+1)st character is a space, 0 otherwise.
Every line in the block whose status is the same as the
status of the first line will begin a new paragraph.
Defaults to 0.
E[<Err>] If <Err> is 1, messages to the user (caused by the help
and version options, or by errors) are sent to the error
stream instead of the output stream. Defaults to 0.
e[<expel>] If <expel> is 1, superfluous lines withheld from the
output. Defaults to 0.
f[<fit>] If <fit> is 1 and <just> is 0, par tries to make the
lines in the OP as nearly the same length as possible,
even if it means making the OP narrower. Defaults to 0.
(See also the j option.)
g[<guess>] If <guess> is 1, then when par is choosing line breaks,
whenever it encounters a curious word followed by a
capitalized word, it takes one of two special actions.
If the two words are separated by a single space in
the input, they will be merged into one word with an
embedded non-breaking space. If the two words are
separated by more than one space, or by a line break,
par will insure that they are separated by two spaces,
or by a line break, in the output. Defaults to 0.
i[<invis>] If <invis> is 1, then vacant lines inserted because
<quote> is 1 are invisible; that is, they are not
output. If <quote> is 0, <invis> has no effect.
Defaults to 0. (See also the q option.)
j[<just>] If <just> is 1, par justifies the OP, inserting spaces
between words so that all lines in the OP have length
<width> (except the last, if <last> is 0). Defaults to
0. (See also the w, l, and f options.)
l[<last>] If <last> is 1, par tries to make the last line of the
OP about the same length as the others. Defaults to 0.
q[<quote>] If <quote> is 1, then before each segment is scanned
for bodiless lines, par supplies vacant lines between
different quotation nesting levels as follows: For each
pair of adjacent lines in the segment (scanned from the
top down) which have different quoteprefixes, one of
two actions is taken. If <invis> is 0, and either line
consists entirely of quote characters and spaces (or is
empty), that line is truncated to the longest common
prefix of the two lines (both are truncated if both
qualify). Otherwise, a line consisting of the longest
common prefix of the two lines is inserted between them.
<quote> also affects the default value of <prefix>.
Defaults to 0. (See also the p and i options.)
R[<Report>] If <Report> is 1, it is considered an error for an input
word to contain more than <L> = (<width> - <prefix> -
<suffix>) characters. Otherwise, such words are chopped
after each <L>th character into shorter words. Defaults
to 0.
t[<touch>] Has no effect if <suffix> is 0 or <just> is 1.
Otherwise, if <touch> is 0, all lines in the OP have
length <width>. If <touch> is 1, the length of the
lines is decreased until the suffixes touch the body of
the OP. Defaults to the logical OR of <fit> and <last>.
(See also the s, j, w, f, and l options.)
If an argument begins with a number, that number is assumed
to belong to a p option if it is 8 or less, and to a w option
otherwise.
If the value of any parameter is set more than once, the last value
is used. When unset parameters are assigned default values, <hang>
and <quote> are assigned before <prefix>, and <fit> and <last> are
assigned before <touch> (because of the dependencies).
It is an error if <width> <= <prefix> + <suffix>.
Environment
PARBODY Determines the initial set of body characters (which are
used for determining comprelens and comsuflens), using
charset syntax. If PARBODY is not set, the set of body
characters is initially empty.
PARINIT If set, par will read command line arguments from PARINIT
before it reads them from the command line. Within
the value of PARINIT, arguments are separated by white
characters.
PARPROTECT Determines the set of protective characters, using charset
syntax. If PARPROTECT is not set, the set of protective
characters is initially empty.
PARQUOTE Determines the set of quote characters, using charset
syntax. If PARQUOTE is not set, the set of quote characters
initially contains only the greater-than sign (>) and the
space.
If a NUL character appears in the value of an environment variable, it
and the rest of the string will not be seen by par.
Note that the PARINIT variable, together with the B, P, and Q
options, renders the other environment variables unnecessary. They
are included for backward compatibility.
Details
Lines are terminated by newline characters, but the newlines are not
considered to be included in the lines. If the last character of
the input is a non-newline, a newline will be inferred immediately
after it (but if the input is empty, no newline will be inferred;
the number of input lines will be 0). Thus, the input can always be
viewed as a sequence of lines.
Protected lines are copied unchanged from the input to the output.
All other input lines, as they are read, have any NUL characters
removed, and every white character (except newlines) turned into a
space. Actually, each tab character is turned into <Tab> - (<n> %
<Tab>) spaces, where <n> is the number of characters preceeding the
tab character on the line (evaluated after earlier tab characters
have been expanded).
Blank lines in the input are transformed into empty lines in the
output.
If <repeat> is 0, all bodiless lines are vacant, and they are all
simply stripped of trailing spaces before being output. If <repeat>
is not 0, only vacant lines whose suffixes have length 0 are treated
that way; other bodiless lines have the number of instances of their
repeat characters increased or decreased until the length of the
line is <width>.
If <expel> is 1, superfluous lines are not output. If <quote> and
<invis> are both 1, there may be invisible lines; they are not
output.
The input is divided into segments, which are divided into blocks,
which are divided into IPs. The exact process depends on the values
of <quote> and <div> (see q and d in the Options section). The
remainder of this section describes the process which is applied
independently to each IP to construct the corresponding OP.
After the values of the parameters are determined (see the Options
section), the first <prefix> characters and the last <suffix>
characters of each input line are removed and remembered. It is
an error for any line to contain fewer than <prefix> + <suffix>
characters.
The remaining text is treated as a sequence of characters, not
lines. The text is broken into words, which are separated by
spaces. That is, a word is a maximal sub-sequence of non-spaces.
If <guess> is 1, some words might be merged (see g in the Options
section). The first word includes any spaces that preceed it on the
same line.
Let <L> = <width> - <prefix> - <suffix>.
If <Report> is 0, some words may get chopped up at this point (see R
in the Options section).
The words are reassembled, preserving their order, into lines. If
<just> is 0, adjacent words within a line are separated by a single
space (or sometimes two if <guess> is 1), and line breaks are chosen
so that the paragraph satisfies the following properties:
1) No line contains more than <L> characters.
2) If <fit> is 1, the difference between the lengths of the
shortest and longest lines is as small as possible.
3) The shortest line is as long as possible, subject to
properties 1 and 2.
4) Let <target> be <L> if <fit> is 0, or the length of the
longest line if <fit> is 1. The sum of the squares of the
differences between <target> and the lengths of the lines is
as small as possible, subject to properties 1, 2, and 3.
If <last> is 0, the last line does not count as a line for the
purposes of properties 2, 3, and 4 above.
If all the words fit on a single line, the properties as worded
above don't make much sense. In that case, no line breaks are
inserted.
If <just> is 1, adjacent words within a line are separated by one
space (or sometimes two if <guess> is 1) plus zero or more extra
spaces. The value of <fit> is disregarded, and line breaks are
chosen so that the paragraph satisfies the following properties:
1) Every line contains exactly <L> characters.
2) The largest inter-word gap is as small as possible, subject
to property 1. (An inter-word gap consists only of the
extra spaces, not the regular spaces.)
3) The sum of the squares of the lengths of the inter-word gaps
is as small as possible, subject to properties 1 and 2.
If <last> is 0, the last line does not count as a line for the
purposes of property 1, and it does not require or contain any
extra spaces.
Extra spaces are distributed as uniformly as possible among the
inter-word gaps in each line.
In a justified paragraph, every line must contain at least two
words, but that's not always possible to accomplish. If the
paragraph cannot be justified, it is considered an error.
If the number of lines in the resulting paragraph is less than
<hang>, empty lines are added at the end to bring the number of
lines up to <hang>.
If <just> is 0 and <touch> is 1, <L> is changed to be the length of
the longest line.
If <suffix> is not 0, each line is padded at the end with spaces to
bring its length up to <L>.
To each line is prepended <prefix> characters. Let <n> be the
number of lines in the IP, let <afp> be the augmented fallback
prelen of the IP, and let <fs> be the fallback suflen of the IP.
The characters which are prepended to the <i>th line are chosen as
follows:
1) If <i> <= <n>, the characters are copied from the ones that were
removed from the beginning of the <n>th input line.
2) If <i> > <n> > <hang>, the characters are copied from the ones
that were removed from the beginning of the last input line.
3) If <i> > <n> and <n> <= <hang>, the first min(<afp>,<prefix>)
of the characters are copied from the ones that were removed
from the beginning of the last input line, and the rest are all
spaces.
Then to each line is appended <suffix> characters. The characters
which are appended to the <i>th line are chosen as follows:
1) If <i> <= <n>, the characters are copied from the ones that were
removed from the end of the nth input line.
2) If <i> > <n> > <hang>, the characters are copied from the ones
that were removed from the end of the last input line.
3) If <i> > <n> and <n> <= <hang>, the first min(<fs>,<suffix>)
of the characters are copied from the ones that were removed
from the beginning of the last input line, and the rest are all
spaces.
Finally, the lines are printed to the output as the OP.
Diagnostics
If there are no errors, par returns EXIT_SUCCESS (see <stdlib.h>).
If there is an error, an error message will be printed to the
output, and par will return EXIT_FAILURE. If the error is local
to a single paragraph, the preceeding paragraphs will have been
output before the error was detected. Line numbers in error
messages are local to the IP in which the error occurred. All
error messages begin with "par error:" on a line by itself. Error
messages concerning command line or environment variable syntax are
accompanied by the same usage message that the help option produces.
Of course, trying to print an error message would be futile if an
error resulted from an output function, so par doesn't bother doing
any error checking on output functions.
Examples
The superiority of par's dynamic programming algorithm over a greedy
algorithm (such as the one used by fmt) can be seen in the following
example:
Original paragraph (note that each line begins with 8 spaces):
We the people of the United States,
in order to form a more perfect union,
establish justice,
insure domestic tranquility,
provide for the common defense,
promote the general welfare,
and secure the blessing of liberty
to ourselves and our posterity,
do ordain and establish the Constitution
of the United States of America.
After a greedy algorithm with width = 39:
We the people of the United
States, in order to form a more
perfect union, establish
justice, insure domestic
tranquility, provide for the
common defense, promote the
general welfare, and secure the
blessing of liberty to
ourselves and our posterity, do
ordain and establish the
Constitution of the United
States of America.
After "par 39":
We the people of the United
States, in order to form a
more perfect union, establish
justice, insure domestic
tranquility, provide for the
common defense, promote the
general welfare, and secure
the blessing of liberty to
ourselves and our posterity,
do ordain and establish the
Constitution of the United
States of America.
The line breaks chosen by par are clearly more eye-pleasing.
par is most useful in conjunction with the text-filtering features
of an editor, such as the ! commands of vi. You may wish to add the
following lines to your .exrc file:
" use Bourne shell for speed:
set shell=/bin/sh
"
" reformat paragraph with no arguments:
map ** {!}par^M}
"
" reformat paragraph with arguments:
map *^V {!}par
Note that the leading spaces must be removed, and that what is shown
as ^M and ^V really need to be ctrl-M and ctrl-V. Also note that
the last map command contains two spaces following the ctrl-V, plus
one at the end of the line.
To reformat a simple paragraph delimited by blank lines in vi, you
can put the cursor anywhere in it and type "**" (star star). If
you need to supply arguments to par, you can type "* " (star space)
instead, then type the arguments.
The rest of this section is a series of before-and-after pictures
showing some typical uses of par. In all cases, no environment
variables are set.
Before:
/* We the people of the United States, */
/* in order to form a more perfect union, */
/* establish justice, */
/* insure domestic tranquility, */
/* provide for the common defense, */
/* promote the general welfare, */
/* and secure the blessing of liberty */
/* to ourselves and our posterity, */
/* do ordain and establish the Constitution */
/* of the United States of America. */
After "par 59":
/* We the people of the United States, in */
/* order to form a more perfect union, establish */
/* justice, insure domestic tranquility, provide */
/* for the common defense, promote the general */
/* welfare, and secure the blessing of liberty */
/* to ourselves and our posterity, do ordain */
/* and establish the Constitution of the United */
/* States of America. */
Or after "par 59f":
/* We the people of the United States, */
/* in order to form a more perfect union, */
/* establish justice, insure domestic */
/* tranquility, provide for the common */
/* defense, promote the general welfare, */
/* and secure the blessing of liberty to */
/* ourselves and our posterity, do ordain */
/* and establish the Constitution of the */
/* United States of America. */
Or after "par 59l":
/* We the people of the United States, in */
/* order to form a more perfect union, establish */
/* justice, insure domestic tranquility, */
/* provide for the common defense, promote */
/* the general welfare, and secure the */
/* blessing of liberty to ourselves and our */
/* posterity, do ordain and establish the */
/* Constitution of the United States of America. */
Or after "par 59lf":
/* We the people of the United States, */
/* in order to form a more perfect union, */
/* establish justice, insure domestic */
/* tranquility, provide for the common */
/* defense, promote the general welfare, */
/* and secure the blessing of liberty */
/* to ourselves and our posterity, do */
/* ordain and establish the Constitution */
/* of the United States of America. */
Or after "par 59lft0":
/* We the people of the United States, */
/* in order to form a more perfect union, */
/* establish justice, insure domestic */
/* tranquility, provide for the common */
/* defense, promote the general welfare, */
/* and secure the blessing of liberty */
/* to ourselves and our posterity, do */
/* ordain and establish the Constitution */
/* of the United States of America. */
Or after "par 59j":
/* We the people of the United States, in */
/* order to form a more perfect union, establish */
/* justice, insure domestic tranquility, provide */
/* for the common defense, promote the general */
/* welfare, and secure the blessing of liberty */
/* to ourselves and our posterity, do ordain and */
/* establish the Constitution of the United */
/* States of America. */
Or after "par 59jl":
/* We the people of the United States, */
/* in order to form a more perfect */
/* union, establish justice, insure domestic */
/* tranquility, provide for the common defense, */
/* promote the general welfare, and secure */
/* the blessing of liberty to ourselves and */
/* our posterity, do ordain and establish the */
/* Constitution of the United States of America. */
Before:
Preamble We the people of the United States,
to the US in order to form
Constitution a more perfect union,
establish justice,
insure domestic tranquility,
provide for the common defense,
promote the general welfare,
and secure the blessing of liberty
to ourselves and our posterity,
do ordain and establish
the Constitution
of the United States of America.
After "par 52h3":
Preamble We the people of the United
to the US States, in order to form a
Constitution more perfect union, establish
justice, insure domestic
tranquility, provide for the
common defense, promote the
general welfare, and secure
the blessing of liberty to
ourselves and our posterity,
do ordain and establish the
Constitution of the United
States of America.
Before:
1 We the people of the United States,
2 in order to form a more perfect union,
3 establish justice,
4 insure domestic tranquility,
5 provide for the common defense,
6 promote the general welfare,
7 and secure the blessing of liberty
8 to ourselves and our posterity,
9 do ordain and establish the Constitution
10 of the United States of America.
After "par 59p12l":
1 We the people of the United States, in order to
2 form a more perfect union, establish justice,
3 insure domestic tranquility, provide for the
4 common defense, promote the general welfare,
5 and secure the blessing of liberty to ourselves
6 and our posterity, do ordain and establish the
7 Constitution of the United States of America.
Before:
> > We the people
> > of the United States,
> > in order to form a more perfect union,
> > establish justice,
> > ensure domestic tranquility,
> > provide for the common defense,
>
> Promote the general welfare,
> and secure the blessing of liberty
> to ourselves and our posterity,
> do ordain and establish
> the Constitution of the United States of America.
After "par 52":
> > We the people of the United States, in
> > order to form a more perfect union,
> > establish justice, ensure domestic
> > tranquility, provide for the common
> > defense,
>
> Promote the general welfare, and secure
> the blessing of liberty to ourselves and
> our posterity, do ordain and establish
> the Constitution of the United States of
> America.
Before:
> We the people
> of the United States,
> in order to form a more perfect union,
> establish justice,
> ensure domestic tranquility,
> provide for the common defense,
> Promote the general welfare,
> and secure the blessing of liberty
> to ourselves and our posterity,
> do ordain and establish
> the Constitution of the United States of America.
After "par 52d":
> We the people of the United States,
> in order to form a more perfect union,
> establish justice, ensure domestic
> tranquility, provide for the common
> defense,
> Promote the general welfare, and secure
> the blessing of liberty to ourselves and
> our posterity, do ordain and establish
> the Constitution of the United States of
> America.
Before:
# 1. We the people of the United States.
# 2. In order to form a more perfect union.
# 3. Establish justice, ensure domestic
# tranquility.
# 4. Provide for the common defense
# 5. Promote the general welfare.
# 6. And secure the blessing of liberty
# to ourselves and our posterity.
# 7. Do ordain and establish the Constitution.
# 8. Of the United States of America.
After "par 37p13dh":
# 1. We the people of the
# United States.
# 2. In order to form a more
# perfect union.
# 3. Establish justice,
# ensure domestic
# tranquility.
# 4. Provide for the common
# defense
# 5. Promote the general
# welfare.
# 6. And secure the blessing
# of liberty to ourselves
# and our posterity.
# 7. Do ordain and establish
# the Constitution.
# 8. Of the United States of
# America.
Before:
/*****************************************/
/* We the people of the United States, */
/* in order to form a more perfect union, */
/* establish justice, insure domestic */
/* tranquility, */
/* */
/* */
/* [ provide for the common defense, ] */
/* [ promote the general welfare, ] */
/* [ and secure the blessing of liberty ] */
/* [ to ourselves and our posterity, ] */
/* [ ] */
/* */
/* do ordain and establish the Constitution */
/* of the United States of America. */
/******************************************/
After "par 42r":
/********************************/
/* We the people of the */
/* United States, in order to */
/* form a more perfect union, */
/* establish justice, insure */
/* domestic tranquility, */
/* */
/* */
/* [ provide for the common ] */
/* [ defense, promote the ] */
/* [ general welfare, and ] */
/* [ secure the blessing of ] */
/* [ liberty to ourselves ] */
/* [ and our posterity, ] */
/* [ ] */
/* */
/* do ordain and establish the */
/* Constitution of the United */
/* States of America. */
/********************************/
Or after "par 42re":
/********************************/
/* We the people of the */
/* United States, in order to */
/* form a more perfect union, */
/* establish justice, insure */
/* domestic tranquility, */
/* */
/* [ provide for the common ] */
/* [ defense, promote the ] */
/* [ general welfare, and ] */
/* [ secure the blessing of ] */
/* [ liberty to ourselves ] */
/* [ and our posterity, ] */
/* */
/* do ordain and establish the */
/* Constitution of the United */
/* States of America. */
/********************************/
Before:
Joe Public writes:
> Jane Doe writes:
> >
> >
> > I can't find the source for uncompress.
> Oh no, not again!!!
>
>
> Isn't there a FAQ for this?
>
>
That wasn't very helpful, Joe. Jane,
just make a link from uncompress to compress.
After "par 40q":
Joe Public writes:
> Jane Doe writes:
>
>
> > I can't find the source for
> > uncompress.
>
> Oh no, not again!!!
>
>
> Isn't there a FAQ for this?
>
That wasn't very helpful, Joe.
Jane, just make a link from
uncompress to compress.
Or after "par 40qe":
Joe Public writes:
> Jane Doe writes:
>
> > I can't find the source for
> > uncompress.
>
> Oh no, not again!!!
>
> Isn't there a FAQ for this?
That wasn't very helpful, Joe.
Jane, just make a link from
uncompress to compress.
Or after "par 40qi":
Joe Public writes:
> Jane Doe writes:
> >
> >
> > I can't find the source for
> > uncompress.
> Oh no, not again!!!
>
>
> Isn't there a FAQ for this?
>
>
That wasn't very helpful, Joe.
Jane, just make a link from
uncompress to compress.
Or after "par 40qie":
Joe Public writes:
> Jane Doe writes:
> > I can't find the source for
> > uncompress.
> Oh no, not again!!!
>
> Isn't there a FAQ for this?
That wasn't very helpful, Joe.
Jane, just make a link from
uncompress to compress.
Before:
I sure hope there's still room
in Dr. Jones' section of archaeology.
I've heard he's the bestest. [sic]
After "par 50g":
I sure hope there's still room in
Dr. Jones' section of archaeology. I've
heard he's the bestest. [sic]
Or after "par 50gc":
I sure hope there's still room in
Dr. Jones' section of archaeology. I've
heard he's the bestest. [sic]
Before:
John writes:
: Mary writes:
: + Anastasia writes:
: + > Hi all!
: + Hi Ana!
: Hi Ana & Mary!
Please unsubscribe me from alt.hello.
After "par Q+:+ q":
John writes:
: Mary writes:
:
: + Anastasia writes:
: +
: + > Hi all!
: +
: + Hi Ana!
:
: Hi Ana & Mary!
Please unsubscribe me from alt.hello.
Before:
amc> The b option was added primarily to deal with
amc> this new style of quotation
amc> which became popular after Par 1.41 was released.
amc>
amc> Par still pays attention to body characters.
amc> Par should not mistake "Par" for part of the prefix.
amc> Par should not mistake "." for a suffix.
After "par B=._A_a 50bg":
amc> The b option was added primarily to
amc> deal with this new style of quotation
amc> which became popular after Par 1.41
amc> was released.
amc>
amc> Par still pays attention to body
amc> characters. Par should not mistake
amc> "Par" for part of the prefix. Par
amc> should not mistake "." for a suffix.
Limitations
The <guess> feature guesses wrong in cases like the following:
I calc'd the approx.
Fermi level to 3 sig. digits.
With <guess> = 1, par will incorrectly assume that "approx." ends a
sentence. If the input were:
I calc'd the approx. Fermi
level to 3 sig. digits.
then par would refuse to put a line break between "approx." and
"Fermi" in the output, mainly to avoid creating the first situation
(in case the paragraph were to be fed back through par again).
This non-breaking space policy does come in handy for cases like
"Mr. Johnson" and "Jan. 1", though.
The <guess> feature only goes one way. par can preserve wide
sentence breaks in a paragraph, or remove them, but it can't insert
them if they aren't already in the input.
If you use tabs, you may not like the way par handles (or doesn't
handle) them. It expands them into spaces. I didn't let par output
tabs because tabs don't make sense. Not everyone's terminal has
the same tab settings, so text files containing tabs are sometimes
mangled. In fact, almost every text file containing tabs gets
mangled when something is inserted at the beginning of each line
(when quoting e-mail or commenting out a section of a shell script,
for example), making them a pain to edit. In my opinion, the
world would be a nicer place if everyone stopped using tabs, so
I'm doing my part by not letting par output them. (Thanks to
ets1@cs.wustl.edu (Eric T. Stuebe) for showing me the light about
tabs.)
There is currently no way for the length of the output prefix to
differ from the length of the input prefix. Ditto for the suffix.
I may consider adding this capability in a future release, but right
now I'm not sure how I'd want it to work.
Apologies
Par began in July 1993 as a small program designed to do one narrow
task: reformat a single paragraph that might have a border on either
side. It was pretty clean back then. Over the next three months,
it very rapidly expanded to handle multiple paragraphs, offer more
options, and take better guesses, at the cost of becoming extremely
complex, and very unclean. It is nowhere near the optimal design
for the larger task it now tries to address. Its only redeeming
features are that it is extremely useful (I find it indispensable),
extremely portable, and very stable (between the release of version
1.41 on 31 Oct 1993 and the release of version 1.50 on 11 Feb 1996,
no bugs were reported).
Back in 1993 I had very little experience at writing documentation
for users, so the documentation for Par became rather nightmarish.
There is no separation between how-it-works (which is painfully
complex) and how-to-use-it (which is fairly simple, if you can ever
figure it out).
Someday I ought to reexamine the problem, and redesign a new, clean
solution from scratch. I don't know when I might get enough free
time to start on such a project. Text files may be obsolete by
then.
Bugs
If I knew of any bugs, I wouldn't release the package. Of course,
there may be bugs that I haven't yet discovered.
If you find any bugs (in the program or in the documentation), or if
you have any suggestions, please send e-mail to:
amc@cs.wustl.edu
or send paper mail to:
Adam M. Costello
Campus Box 1115
Washington University
One Brookings Dr.
St. Louis, MO 63130-4899
USA
When reporting a bug, please include the exact input and command
line options used, and the version number of par, so that I can
reproduce it.
The latest release of Par is available on the Web at:
http://www.cs.wustl.edu/~amc/Par/
Note that all of these addresses could change anytime after August
1996. I'll try to leave forward pointers.