Conlang: Language construction utilities

This project is a collection of tools for working on constructed languages (currently, there is only one tool, but in the future, I plan to include more).

Soundchanger

The sounds package and the soundchanger program provide tools to apply lists of sound changes to words. This tool can be used in diachronic conlanging to systematically evolve words from one language to another, or to apply synchronic changes.

How to use

Sound change files

Sound change files used by this program are read line-by-line. Each line can be one of the following:

A sound change rule

A sound change rule has three parts:

• The change, written as a > b, meaning that a will become b
• The environment, written as  / c_d, meaning that the change will only occur when a occurs between c and d
• The negative environment, written as  ! e_f, meaning that the change will not occur if a occurs after e or before f

Only the change is required, the other two sections are optional.

For the original sound, the environment, and the negative environment (components a, c, d, e, and f of the rule), Regular Expression syntax can be used. This program includes some additional features as well:

• Categories: Categories, which represent a set of sounds, can be included using the syntax {categoryName}, which will match any element of the category. Categories must be defined before they are used, as described below
• Numbered categories: Categories can also be numbered, which forces all categories with the same number to match the same element index. For example, if N is the category m n ŋ, and P is the category p t k, {0:N}{0:P} will match mp, nt, and ŋk, but not things like mt or ŋp (those would still be matched by {N}{P})
  • If a numbered category is included in the result of the sound change (component b), it will be replaced by the appropriate value of that category. For example (continuing from above), the rule {0:P} > {0:N} will cause p to become m, t to become n, and k to become ŋ.
• Word boundaries: The standard Regex \b only correctly matches ASCII word boundaries, which is generally not sufficient for conlinguists who make heavy use of Unicode. Instead, this program offers the character #, which can be used to match word boundaries in the environment or negative environment of a rule. It matches only a boundary between whitespace and non-whitespace.

A category definition

A category definition has the following format: name = elements, where name is the name of the category, and elements is a whitespace-separated list of the elements of that category. A category can also include another (previously-defined) category as an element, in which case that category is expanded into its elements, which are then included.

A comment

A comment is a line that starts with //. It has no effect on the running of the program, but will be output with the debugging info to provide context. Writing comments is highly recommended, as it makes it easier to tell at a glance what each rule is supposed to do. (Source: personal experience)

A blank line

Blank lines are ignored.

soundchanger

The soundchanger program is a simple tool to apply one or more sound change files to words.

Basic usage

soundchanger [-v] [-q] [-p _prefix_] _pairs_

• -v verbose mode: output debug info as along with the words
• -q quiet mode: don't print initial prompt
• -p prefix: use prefix as a prefix before all filenames
• pairs: a list of whitespace-separated pairs of languages, as described below

Once soundchanger is running, it reads lines from stdin, applies changes, and outputs on stdout. Note that if you update any of the sound change files while soundchanger is running, it will automatically re-read the file, so you don't need to restart the program in this case.

File structure

To describe language trees, soundchanger uses dot-separated file names for sound changes. For example, a set of files for describing the changes from Latin to the Romance Languages might something like this (this is of course heavily simplified for use as an example):

latin
latin.ecclesiastical
latin.vulgar
latin.vulgar
latin.vulgar.french
latin.vulgar.french.creyol
latin.vulgar.iberian
latin.vulgar.iberian.portuguese
latin.vulgar.iberian.spanish
latin.vulgar.italian
latin.vulgar.romanian

Then, to apply changes to arrive at Spanish from Latin, you would apply the files latin.vulgar, latin.vulgar.iberian, and latin.vulgar.iberian.spanish in order. To simplify this task, you can instead specify the start and end point of this chain, in this case latin and latin.vulgar.iberian.spanish, and soundchanger will automatically apply all the files in the correct sequence. So the full invocation of soundchanger would be:

soundchanger latin latin.vulgar.iberian.spanish