rmutt.js has a command-line interface which accepts a rmutt grammar as an input. Install it:
$ npm install --global rmutt
node.js is a prerequisite.
The general form to use it is:
$ rmutt [gramarfile] [options]
rmutt does not require any filename extension, but often you'll see we arbitrarily use
.rm.
If you have a file with an rmutt grammar on it, you can mention it on the command line like this:
$ rmutt myfile.rm
If you want to save the output to a file you can simply redirect it:
$ rmutt myfile.rm > myoutputfile
Both grammar file and options are not required.
If you have a program which generates an rmutt grammar, you can pipe it through rmutt command. For example:
$ echo "night-sky:('.' 5, ' ' 100, '*'){100000};" | rmutt
(without double quotes in Windows)
Output usage information and exit.
Output version and exit.
If specified, load or create a cached transpiled code file.
Absolute path and file name where the transpiled code will be cached.
If specified, write the transpiled file even if it already exists.
In order to produce a string, rmutt must start with one of the rules in the grammar. By default, rmutt expands the first rule it finds in the grammar, but you can use this option to specify another one.
A given rmutt grammar can generate N possible strings, where N is finite or infnite depending on whether or not the grammar is recursive. Specifying an iteration will deterministically generate the N-th possible string. If the iteration specified (call it i) is greater than N, rmutt will generate the i mod Nth iteration. Enumerating all possible strings of a grammar is usually only useful for very simple grammars; most grammars can produce more strings than can be enumerated with a JavaScript number.
Specifies the maximum depth to which rmutt will expand the grammar. This is usually used to prevent recursive grammars from crashing rmutt with stack overflows. Beyond the maximum stack depth, a rule will expand to an empty, zero-length string.
Specifies a seed for the random number generator. Two runs against the same grammar with the same seed will generate identical output. The seed must be a 32-bit integer. If no seed is specified, a seed is generated and can be expanded in the grammar using the $options.randomSeed rule.
Output transpiled code instead of rule expansion.