zoem(1) USER COMMANDS zoem(1)
1. NAME
2. SYNOPSIS
3. DESCRIPTION
4. OPTIONS
5. SESSION MACROS
6. THE SET MODIFIERS
7. THE INSPECT SUBLANGUAGE
8. THE TR SUBLANGUAGE
9. TILDE EXPANSION
10. ENVIRONMENT
11. DIAGNOSTICS
12. BUGS
13. SEE ALSO
14. EXAMPLES
15. AUTHOR
NAME
zoem - macro processor for the Zoem macro/programming language.
SYNOPSIS
zoem [-i <file name>[.azm] (entry file name)] [-I <file name> (entry file name)] [-o <file name> (output file name)] [-d <device> (set
device key)]
zoem
(enter interactive mode - happens when none of -i, -I, -o is given)
zoem -i <file name>[.azm] (entry file name) -I <file name> (entry file name) [-o <file name> (output file name)] [-d <device> (set device
key)] [-x (enter interactive mode on error)] [-s <key>[=<val>] (set key to val)] [-e <any> (evaluate any, exit)] [-E <any> (evaluate any,
proceed)] [-chunk-size <num> (process chunks of size num)] [--trace (trace mode, default)] [--trace-all-long (long trace mode)] [--trace-
all-short (short trace mode)] [--trace-regex (trace regexes)] [-trace k (trace mode, explicit)] [--stats (show symbol table stats after
run)] [--split (assume writeto usage, set \__split__)] [--stress-write (make write#3 recover)] [--unsafe (prompt for system#3)]
[--unsafe-silent (simply allow system#3)] [-allow cmd1[:cmdx]+ (allowable commands)] [--system-honor (require system#3 to succeed)]
[-nuser k (user dict stack size)] [-nenv k (environment dict stack size)] [-nsegment k (maximum simple nesting depth)] [-nstack k (maximum
eval nesting depth)] [-buser (initial user dict capacity)] [-bzoem (initial zoem dict capacity)] [-tl k (tab length)] [-l <str> (list
items)] [-h (show options)] [--apropos (show options)]
DESCRIPTION
Zoem is a macro/programming language. It is fully described in the Zoem User Manual (zum.html), currently available in HTML only. This man-
ual page documents the zoem processor, not the zoem language.
If the input file is specified using the -i option and is a regular file (i.e. not STDIN - which is specified by using a single hyphen), it
must have the extension .azm. This extension can but need not be specified. The zoem key \__fnbase__ will be set to the file base name
stripped of the .azm extension and any leading path components. If the input file is specified using the -I option, no extension is
assumed, and \__fnbase__ is set to the file base name, period. The file base name is the file name with any leading path components stripped
away.
If neither -i nor -o is specified, zoem enters interactive mode. Zoem should fully recover from any error it encounters in the input. If
you find an exception to this rule, consider filing a bug report. In interactive mode, zoem start interpreting once it encounters a line
containing a single dot. Zoem's input behaviour can be modified by setting the key \__parmode__. See the section SESSION MACROS for the
details. In interactive mode, zoem does not preprocess the interactive input, implying that it does not accept inline files and it does not
recognize comments. Both types of sequence will generate syntax errors. Finally, readline editing and history retrieval can be used in
interactive mode provided that they are available on the system. This means that the input lines can be retrieved, edited, and discarded
with a wide range of cursor positioning and text manipulation commands.
From within the entry file and included files it is possible to open and write to arbitrary files using the write#3 primitive. Arbitrary
files can be read in various modes using the dofile#2 macro (providing four different modes with respect to file existence and output),
finsert#1, and zinsert#1. Zoem will write the default output to a single file, the name of which is either specified by the -o option, or
constructed as described below. Zoem can split the default output among multiple files. This is governed from within the input files by
issuing writeto#1 calls. Refer to the --split option and the Zoem User Manual.
If none of -i or -o is given, then zoem will enter interactive mode. In this mode, zoem interprets by default chunks of text that are ended
by a single dot on a line of its own. This can be useful for testing or debugging. In interactive mode, zoem should recover from any failure
it encounters. Interactive mode can also be accessed from within a file by issuing zinsert{stdia}, and it can be triggered as the mode to
enter should an error occur (by adding the -x option to the command line).
If -o is given and -i is not, zoem reads input from STDIN.
If -i is given and -o is not, zoem will construct an output file name as follows. If the -d option was used with argument <dev>, zoem will
write to the file which results from expanding \__fnbase__.<dev>. Otherwise, zoem writes to (the expansion of) \__fnbase__.ozm.
For -i and -o, the argument - is interpreted as respectively stdin and stdout.
OPTIONS
-i <file name>[.azm] (entry file name)
Specify the entry file name. The file must have the .azm extension, but it need not be specified.
-I <file name>[.azm] (entry file name)
Specify the entry file name, without restrictions on the file name.
-o <file name> (output file name)
Specify the output file name.
-d <device> (set key \__device__)
Set the key \__device__ to <device>.
-x (enter interactive mode on error)
The afterlife option. If zoem encounters an error during regular processing, it will emit error messages as usual, and then enter interac-
tive mode. This allows you e.g. to inspect the values of keys used or defined within the problematic area.
-s <key>[=<val>] (set key to val)
Set the key key to val if present, 1 otherwise. Any type of key can be set, including keys taking arguments and keys surrounded in
quotes. Beware of the shell's quote and backslash interpolation. Currently val is not evaluated, so appending or prepending to a key is
not possible.
-e <any> (evaluate any, exit)
This causes zoem to evaluate <any>, write any result text to stdout, and exit.
-E <any> (evaluate any, proceed)
This causes zoem to evaluate <any>, write any result text to stdout, and proceed e.g. with the entry file or an interactive session.
-chunk-size <num> (process chunks of size num)
Zoem reads its input in chunks. It fully processes a chunk before moving on with the next one. This option defines the (minimum) size of
the chunks. The size or count of the chunks does not at all affect zoem's output. The default minimum chunk size equals one megabyte.
Zoem will read files in their entirety before further processing if -chunk-size 0 is specified.
Zoem does not chunk input files arbitrarily. It will append to a chunk until it is in the outermost scope (not contained within any block)
and the chunk will end with a line that was fully read.
Consequently, if e.g. a file contains a block (delimited by balanced curlies) spanning the entire file then zoem is forced to read it in
its entirety.
--trace (trace mode, default)
Trace in default mode.
--trace-all-long (long trace mode)
Sets on most trace options in long mode. Trace options xxx not set have their own --trace-xxx entry (see below).
--trace-all-short (short trace mode)
Sets on most trace options in short mode. Trace options xxx not set have their own --trace-xxx entry (see below).
--trace-keys (trace keys)
Trace keys.
--trace-regex (trace regexes)
Trace regexes (i.e. the inspect#4 primitive).
-trace k (trace mode, explicit)
Set trace options by adding their representing bits.
--stress-write (stress test using write)
This makes write#3 recover from errors. It is a special purpose option used for creating zoem stress test suites, such as stress.azm in
the zoem distribution /examples subdirectory.
--unsafe (prompt for system#3)
--unsafe-silent (simply allow system#3)
-allow cmd1[:cmdx]+ (allowable commands)
With --unsafe system calls are allowed but the user is prompted for each invocation. The command and its arguments (if any) are shown, but
the STDIN information (if any) is withheld. With --unsafe-silent system calls are allowed and the user is never prompted.
Use -allow str or --allow=str to specify a list of allowable commands, as a string in which the commands are separated by colons.
--system-honor (require system#3 to succeed)
With this option any system#3 failure (for whatever reason, including safe behaviour) is regarded as a zoem failure. By default, failing
system calls are ignored under either safe mode, unsafe mode (--unsafe), or silent unsafe mode (--unsafe-silent).
--split (assume split output)
This assumes zoem input that allows output to multiple files (e.g. chapters). It sets the default output stream to stdout (anticipating
custom output redirection with writeto#1) and sets the session macro \__split__ to 1.
--stats (show symbol table stats after run)
Show symbol table chacteristics. Symbol tables are maintained as hashes.
-tl k (set tab length)
Set the tab length. HTML output can be indented according to nesting structure, using tabs which are expanded to simple spaces. By
default, the tab length is zero, meaning that no indent is shown. The maximum value the tab length can be set to is four.
-nsegment k (level of macro nesting allowed)
-nstack k (stack count)
-nuser k (user dictionary stack size)
-nenv k (environment dictionary stack size)
-buser k (initial user dict capacity)
-bzoem k (initial zoem dict capacity)
Probably needed only if you have some obscure and extreme use for zoem. The segment limit applies to simple nesting of macros. The stack
limit applies to nesting of macros that evaluate an argument before use. Each such evaluation creates a new stack. The user limit applies
to push{user}, the env limit applies to the nesting level of environments (started with egin#2). The user dict capacity pertains to the
initial number of buckets allocated for user and environment dictionaries, and the zoem dict capacity pertains to the dictionary contain-
ing the zoem primitives.
-l <str> (list items)
List items identified by <str>. It can be any of all, filter. legend, builtin, session, trace, or zoem, Multiple identifiers can be
joined in a string, e.g. -l legendzoem prints a legend followed by a listing of zoem primitives.
-h (show options)
Show short synopsis of options.
SESSION MACROS
\__parmode__
This macro affects zoem's read behaviour in interactive mode. It can be set on the command line using the -s option. Bits that can be
set:
1 chomp newlines (remove the newline character)
2 skip empty newlines
4 read paragraphs (an empty line triggers input read)
8 newlines can be escaped using a backslash
16 read large paragraphs (a single dot on a line
triggers input read)
\__device__
The current output device, set by the command line option -d. The man and faq packages support html and roff as its values.
\__fnbase__
The base name of the input file name. Leading path components are stripped away. If the -i option is used the input file is required to
have the .azm suffix. In that case the suffix is also stripped to obtain the base name.
\__fnentry__
The name of the entry file.
\__fnin__
The file currently being processed.
\__fnout__
The name of the default output file.
\__fnpath__
The leading component of the input file name, possibly empty.
\__fnup__
The file that included the current file, if applicable.
\__fnwrite__
This key is set by write#3 to its first argument. It can be used by macros that are expanded during evaluation of the third argument.
Possible usage is to branch on the name of the write output stream. For example a file called index.html may be treated differently from
other files. The key is deleted afterwards. Nested invocations of write#3 may corrupt the status of this key.
\__ia__
The input/output separator used in interactive mode.
\__line__
The line number in the file currently being processed. This number will be correct for any invocation outside the scope of a macro. For
any invocation within a macro the result will be the line number of the closing curly of the outermost containing macro. The following
\__line__
\__line__
\__line__
group{
\__line__
group{\__line__}
\__line__}
Results in
1
2
3
7
7
7
\__searchpath__
A vararg containing a list of paths to search when a file is to be included/imported/read/loaded. When you start zoem, this key should
contain the location of the man.zmm and faq.zmm package files. It is advisable not to overwrite this key but to append to it instead.
\__zoemstat__
Set to one of ok, towel (that one is a bit lame), or error by either the interpreter, an occurrence of catch#2, or ry#1.
\__zoemput__
Set by ry#1 to the possibly truncated result of processing its argument.
\__lc__
Expands to a left curly. It is hard to find a need for this - the zoem stress suite uses it to generate a particular syntax error at a
deeper interpretation level.
\__rc__
Expands to a right curly.
THE SET MODIFIERS
The set#3 primitive allows a {modes}{<modifiers>} directive in its first argument. Here <modifiers> can be a combination of single-letter
modifiers, each described below.
a append to the key, do not overwrite, create if not existing.
c conditionally; only set if not already defined.
e existing; update existing key, possibly in lower dictionary.
g global; set in the global (bottom) user dictionary.
u unary; do not interpret vararg in <any> as key-value list (data keys only)
v vararg; interpret vararg in <any> as key-value list (regular keys only).
w warn if key exists (like def#2 and defx#2).
x expand argument (like setx#2 and defx#2).
THE INSPECT SUBLANGUAGE
The inspect#4 primitive takes four arguments. The languages accepted by the first two arguments are described below. The third argument is
a replacement string or a replacement macro accepting back-references (supplied as an anonymous macro). The fourth argument is the data to
be processed.
arg 1
Is a vararg. Currently it accepts a single key mods for which the value should be a comma-separated list over the words posix, icase,
dotall, iter-lines iter-args, match-once, discard-nmp, discard-nil-out, discard-miss, count-matches. Alternatively repeated use of mods is
allowed.
arg 2
Is a regular expression. Tilde patterns are expanded according to all of the ZOEM, UNIX, and REGEX schemes. Refer to TILDE EXPANSION for
these.
The third argument is a constant string or an anonymous key, the fourth argument is data.
THE TR SUBLANGUAGE
The r#2 primitive takes two arguments. The first argument contains key-value pairs. The accepted keys are from and to which must always
occur together, and delete and squash. The values of these keys must be valid translation specifications. This primitive transforms the
data in the second argument by successively applying translation, deletion and squashing in that order. Only the transformations that are
needed need be specified.
Translation specifications are subjected to UNIX tilde expansion as described below.
The syntax accepted by translation specifications is almost fully compliant with the syntax accepted by tr(1), with three exceptions. First,
repeats are introduced as [*a*20] rather than [a*20]. Second, ranges can (for now) only be entered as X-Y, not as [X-Y]. X and Y can be
entered in either octal or hexadecimal notation (see further below). As an additional feature, the magic repeat operator [*a#] stops on
both class and range boundaries. Character specifications can be complemented by preceding them with the caret ^.
Specifications may contain ranges of characters such as a-z and 0-9. Posix character classes are allowed. The available classes are
[:alnum:]
[:alpha:]
[:cntrl:]
[:digit:]
[:graph:]
[:lower:]
[:print:]
[:punct:]
[:space:]
[:upper:]
[:xdigit:]
Characters can be specified using octal notation, e.g. 12 encodes the newline. Use 173 for the opening curly, 175 for the closing
curly, 134 for the backslash, and 36 for the caret if it is the first character in a specification. DON'T use \, {, or } in this case!
Hexadecimal notation is written as x7b (the left curly in this instance).
See EXAMPLES for an example of tr#2 usage.
TILDE EXPANSION
Some primitives interface with UNIX libraries that require backslash escape sequences to encode certain tokens or characters. The backslash
is special in zoem too and without further measures it can become very cumbersome to encode the correct escape sequences as it is not always
clear which tokens should be escaped or unprotected at what point. It is especially difficult to handle the zoem characters with special
meaning, {, } and .
The two primitives under consideration are inspect#4 and r#2. Both treat the tilde as an additional escape character for certain argu-
ments (as documented in the user manual). These arguments are subjected to tilde expansion, where the tilde and the character it proceeds
are translated to a new character or character sequence. There are three different sets of tilde escapes, ZOEM, UNIX and REGEX escapes.
r#2 only accepts UNIX escapes, inspect#4 accepts all. Tilde expansion is always the last processing step before strings are passed on to
external libraries.
The ZOEM scheme contains some convenience escapes, such as ~E to encode a double backslash.
ZOEM tilde expansion
meta sequence replacement
.-----------------------------.
| ~~ | ~ |
| ~E | \ |
| ~e | |
| ~I | { |
| ~J | } |
| ~x | x |
| ~i | { |
| ~j | } |
`-----------------------------'
The zoem tr specification language accepts x** as hexadecimal notation, e.g. x0a denotes a newline in the ASCII character set.
UNIX tilde expansion
meta sequence replacement
.-----------------------------.
| ~a | a |
| ~b | |
| ~f | f |
| ~n |
|
| ~r |
|
| ~t | |
| ~v | v |
| ~0 | |
| ~1 | 1 |
| ~2 | 2 |
| ~3 | 3 |
`-----------------------------'
REGEX tilde expansion
meta sequence replacement
.-----------------------------.
| ~^ | ^ |
| ~. | . |
| ~[ | [ |
| ~$ | $ |
| ~( | ( |
| ~) | ) |
| ~| | | |
| ~* | * |
| ~+ | + |
| ~? | ? |
`-----------------------------'
ENVIRONMENT
The environment variable ZOEMSEARCHPATH may contain a colon and/or whitespace separated list of paths. It will be used when searching for
files included via one of the dofile aliases input, import,
ead, and load. Note that the zoem macro \__searchpath__ contains the loca-
tion where the zoem macro files were copied at the time of installation of zoem.
DIAGNOSTICS
On error, Zoem prints a file name and a line number to which it was able to trace the error. The number reported is the same as the one
stored in the session macro \__line__. For an error-trigering macro which is not nested within another macro the line number should be cor-
rect. For a macro that does occur nested within another macro the line number will be the line number of the closing curly in the outermost
containing macro.
If in despair, use one of the tracing modes, --trace-keys is one of the first to come to mind. Another possibility is to supply the -x
option.
BUGS
No known bugs. inspect#4 has not received thorough stress-testing, and the more esoteric parts of its interface will probably change.
SEE ALSO
Aephea is a document authoring framework largely for HTML documents.
Portable Unix Documentation provides two mini-languages for authoring in the unix environment. These languages, pud-man and pud-faq are both
written in zoem.
EXAMPLES
This is a relatively new section, aimed at assembling useful or explanatory snippets.
Create a vararg containing file names matching a pattern (png in this example).
setx{images}{
inspect{
{mods}{iter-lines,discard-miss}
}{(.*~.png)}{_#1{{1}}}{system{ls}}
}
Use magic boundary stops with tr#2.
r{
{from}{[:lower:][:upper:][:digit:][:space:][:punct:]}
{to}{[*L#][*U#][*D#][*S#][*P#]}}{
!"#$%&'()*+,-./0123456789:;<=>?@
ABCDEFGHIJKLMNOPQRSTUVWXYZ
[\]^_`
abcdefghijklmnopqrstuvwxyz
{|}~]}
AUTHOR
Stijn van Dongen.
zoem 11-166 15 Jun 2011 zoem(1)