local export = {}
-- Common regex patterns:
export.consonant_list = "kKgGNcCjJYwWqQRtTdDnpPbBmyrlLvSzsh"
export.consonant = "[" .. export.consonant_list .. "]"
export.accent = "[/\\]"
export.vowel_list = "aAiIuUfFxXeEoO"
export.vowel = "[" .. export.vowel_list .. "]"
export.vowel_with_accent = export.vowel .. export.accent .. "?"
-- Abbreviated helper functions:
local U = mw.ustring.char
local match = mw.ustring.match
local gsub = mw.ustring.gsub
local sub = mw.ustring.sub
local lower = mw.ustring.lower
local upper = mw.ustring.upper
--[=[Detects whether a specified text ends in a given pattern.
Parameters:
text (String): the text to be tested
pattern (String): the query pattern to be tested on the end of the text.
Return:
Boolean
]=]
local function ends_with(text, pattern)
return match(text, pattern .. "$")
end
--[=[Detects whether a specified text begins in a given pattern.
Parameters:
text (String): the text to be tested
pattern (String): the query pattern to be tested on the beginning of the text.
Return:
Boolean
]=]
local function starts_with(text, pattern)
return match(text, "^" .. pattern)
end
-- Common transformation types:
--[=[ Increase a vowel one grade (guṇation). It is possible that this should
include provisions for guṇation of sonorants into CV configurations
(e.g. i/ī -> ya -> yā, etc.). Perhaps will need to be updated.
]=]
export.up_one_grade = {
['a'] = 'A', ['A'] = 'A', ['a/'] = 'A/', ['A/'] = 'A/', ['a\\'] = 'A\\', ['A\\'] = 'A\\',
['i'] = 'e', ['I'] = 'e', ['i/'] = 'e/', ['I/'] = 'e/', ['i\\'] = 'e\\', ['I\\'] = 'e\\',
['u'] = 'o', ['U'] = 'o', ['u/'] = 'o/', ['U/'] = 'o/', ['u\\'] = 'o\\', ['U\\'] = 'o\\',
['e'] = 'E', ['E'] = 'E', ['e/'] = 'E/', ['E/'] = 'E/', ['e\\'] = 'E\\', ['E\\'] = 'E\\',
['o'] = 'O', ['O'] = 'O', ['o/'] = 'O/', ['O/'] = 'O/', ['o\\'] = 'O\\', ['O\\'] = 'O\\',
['f'] = 'ar', ['F'] = 'ar', ['f/'] = 'a/r', ['F/'] = 'a/r', ['f\\'] = 'a\\r', ['F\\'] = 'a\\r',
}
-- Decrease vowel one grade (reverse of above)
export.shorten = {
['a'] = 'a', ['A'] = 'a', ['a/'] = 'a/', ['A/'] = 'a/', ['a\\'] = 'a\\', ['A\\'] = 'a\\',
['i'] = 'i', ['I'] = 'i', ['i/'] = 'i/', ['I/'] = 'i/', ['i\\'] = 'i\\', ['I\\'] = 'i\\',
['u'] = 'u', ['U'] = 'u', ['u/'] = 'u/', ['U/'] = 'u/', ['u\\'] = 'u\\', ['U\\'] = 'u\\',
['f'] = 'f', ['F'] = 'f', ['f/'] = 'f/', ['F/'] = 'f/', ['f\\'] = 'f\\', ['F\\'] = 'f\\',
}
-- Lengthen a vowel
export.lengthen = {
['a'] = 'A', ['A'] = 'A', ['a/'] = 'A/', ['A/'] = 'A/', ['a\\'] = 'A\\', ['A\\'] = 'A\\',
['i'] = 'I', ['I'] = 'I', ['i/'] = 'I/', ['I/'] = 'I/', ['i\\'] = 'I\\', ['I\\'] = 'I\\',
['u'] = 'U', ['U'] = 'U', ['u/'] = 'U/', ['U/'] = 'U/', ['u\\'] = 'U\\', ['U\\'] = 'U\\',
['f'] = 'F', ['F'] = 'F', ['f/'] = 'F/', ['F/'] = 'F/', ['f\\'] = 'F\\', ['F\\'] = 'F\\',
}
-- Convert a monosegmental (or at least monoliteral) diphthong into a/ā + glide.
export.split_diphthong = {
['e'] = 'ay', ['e/'] = 'a/y', ['e\\'] = 'a\\y',
['E'] = 'Ay', ['E/'] = 'A/y', ['E\\'] = 'A\\y',
['o'] = 'av', ['o/'] = 'a/v', ['o\\'] = 'a\\v',
['O'] = 'Av', ['O/'] = 'A/v', ['O\\'] = 'A\\v',
}
--[=[Convert a syllabic sonorant to its associated consonantal form. This map is
presently misnamed since the the input is syllabic (not semivocalic)
and since liquids are not semivowels at all.
]=]
export.semivowel_to_cons = {
['i'] = 'y', ['I'] = 'y',
['u'] = 'v', ['U'] = 'v',
['f'] = 'r', ['F'] = 'r',
['x'] = 'l', ['X'] = 'l',
}
-- Add a homorganic glide to a vowel
local insert_glide = {
['i'] = 'iy', ['I'] = 'iy', ['i/'] = 'i/y', ['I/'] = 'i/y', ['i\\'] = 'i\\y', ['I\\'] = 'i\\y',
['u'] = 'uv', ['U'] = 'uv', ['u/'] = 'u/v', ['U/'] = 'u/v', ['u\\'] = 'u\\v', ['U\\'] = 'u\\v',
}
--[=[Convert all unambiguous stops to their absolute final value. The equivalent
values (e.g. k = k) may be redundant given the implementation of
absolute_final and internal_sandhi below.
]=]
local to_final = {
['k'] = 'k', ['K'] = 'k', ['g'] = 'k', ['G'] = 'k',
['w'] = 'w', ['W'] = 'w', ['q'] = 'w', ['Q'] = 'w',
['t'] = 't', ['T'] = 't', ['d'] = 't', ['D'] = 't',
['p'] = 'p', ['P'] = 'p', ['b'] = 'p', ['B'] = 'p',
['Y'] = 'N',
}
-- Convert dental to reptroflex
local dental_to_retroflex = {
['t'] = 'w', ['T'] = 'W', ['d'] = 'q', ['Q'] = 'Q', ['n'] = 'R',
}
-- Remove aspiration
local deaspirate = {
['K'] = 'k', ['G'] = 'g',
['C'] = 'c', ['J'] = 'j',
['W'] = 'w', ['Q'] = 'q',
['T'] = 't', ['D'] = 'd',
['P'] = 'p', ['B'] = 'b',
['h'] = 'g',
}
--[=[Detects whether a word is monosyllabic. This function does not apply sandhi
to determing whether a potential phonemic form like /dā́rv/ would be
syllabified to [dā́ru]. This might need to be changed.
Parameters:
text (String): the text to be checked for monosyllabicity
Return:
Boolean
]=]
function export.is_monosyllabic(text)
return match(text, "^" .. export.consonant .. "*" .. export.vowel .. export.accent .. "?" .. export.consonant .. "*$")
end
--[=[Transforms a word to its absolute final sandhi form.
Parameters:
text (String): the text to be converted to final sandhi position
ambig_hint (String): an indication of what outcome a palatal should have as
final palatals will unpredictably produce either a retroflex or a velar
stop in final position (e.g. spáś- > spáṭ 'spy' vs. náś- > nák 'night').
Required for palatal-final strings.
Return:
String
]=]
local function absolute_final(text, ambig_hint)
if ends_with(text, export.consonant .. export.consonant) then -- at least 2 consonants
-- Take the first of the cluster.
text = gsub(text, "(" .. export.consonant .. "+)$",
function(cluster) return sub(cluster, 1, 1) end)
end
-- ḷ, v, and y are not handled as they should not appear finally. Perhaps wrong.
if ends_with(text, "[kwtpNRnmlaAiIuUeEoOfFxXH][/\\]?") then
-- do nothing
elseif ends_with(text, "M") then -- just in case, ṃ > m
text = gsub(text, ".$", "m")
elseif ends_with(text, "[sr]") then -- convert to final visarga
text = gsub(text, ".$", "H")
elseif ends_with(text, "[KgGWqQTdDPbBY]") then -- Handle final stops.
text = gsub(text, ".$", to_final)
elseif ends_with(text, "[cCjJhSz]") then -- Handle final palatals.
text = gsub(text, ".$", ambig_hint)
end
return text
end
--[=[Applying retroflexion to a stem and ending without joining them.
This include RUKI, ṣ-cluster harmony, and nasal retroflexions.
Parameters:
stem (String): the stem to receive an ending
ending (String): the ending to be affixed
Return:
String (stem), String (ending)
]=]
function export.retroflexion(stem, ending)
-- Does the stem end in a RUKI environment?
if ends_with(stem, "[iIeEfFxuUoOrk][/\\]?[HM]?") then
ending = gsub(ending, "^s([^rfF])", "z%1") -- Convert ending-initial s > ṣ not followed by [rṛṝ].
ending = gsub(ending, "^z[tTdDn]*", function(dentals) return gsub(dentals, ".", dental_to_retroflex) end)
end
-- Does the stem end in a RUKI environment followed by s and the ending not start with [rṛṝ]?
if ends_with(stem, "[iIeEfFxuUoOrk][/\\]?[HM]?s") and starts_with(ending, "[^rfF]") then
stem = gsub(stem, "s$", "z") -- Convert stem-final s > ṣ
end
if ends_with(stem, "z") then -- Does the stem end in ṣ?
-- Convert an ending-initial dental (cluster) to retroflex
ending = gsub(ending, "^[tTdDn]*", function(dentals) return gsub(dentals, ".", dental_to_retroflex) end)
end
-- Does the stem contain a nasal harmony trigger without intervening blockers?
if ends_with(stem, "[zrfF][^cCjJYwWqQRtTdDnSsl]*") then
ending = gsub(ending, -- Convert all retroflexable n > ṇ in the ending
"^([^cCjJYwWqQRtTdDnSsl]*)n([aAiIeEfFxuUoOynmv])",
function(pre, post) -- Does this need to be a function? Why not "%1R%2"? Does it make a difference in speed?
return pre .. "R" .. post
end)
end
-- Does the stem contain a nasal harmony trigger without intervening blockers and stem-final n?
if ends_with(stem, "[zrfF][^cCjJYwWqQRtTdDnSsl]*n") and starts_with(ending, "[aAiIeEfFxuUoOynmv]") then
stem = gsub(stem, "n$", "R") -- Convert stem-final n > ṇ
end
-- For safety, does the ending contain a unblocked nasal harmony trigger and un retroflexed n?
ending = gsub(ending,
"([zrfF][^cCjJYwWqQRtTdDnSsl]*)n([aAiIeEfFxuUoOynmv])",
function(pre, post)
return pre .. "R" .. post -- Again, Why not "%1R%2"?
end)
return stem, ending
end
--[=[Combine a stem and ending while modfiying the accentuation. This does not currently
account for mobility of accent between the stem and ending.
Parameters:
stem (String): the stem to receive an ending
ending (String): the ending to be affixed
has_accent (Boolean): whether the word has an accent to be modified at all
accent_override (Boolean): whether to strip the stem of accent
mono (Boolean): whether the stem is monosyllabic AND susceptible to
accentual mobility (cf. pā́dam ~ padā́ vs. gā́m ~ gávā). This should
perhaps be renamed or removed as redundant to accent_override in this
function. This should not be applied to *all* monosyllabic nouns!
recessive (Boolean): whether the accent must be moved to the leftmost vowel (e.g. in the vocative)
Return:
String
]=]
local function combine_accent(stem, ending, has_accent, accent_override, mono, recessive)
if has_accent then
if recessive then
local combined = stem .. ending -- combine word
combined = gsub(combined, export.accent, "") -- remove any accent
combined = gsub(combined, "^([^" .. export.vowel_list .. "]-)(" .. export.vowel .. ")", "%1%2/") -- accent first vowel of combined form
return combined
elseif accent_override then
stem = gsub(stem, export.accent, "") -- remove all accents from stem
elseif mono and match(ending, export.accent) then
stem = gsub(stem, export.accent, "") -- remove all accents from stem
-- If both the stem and ending are accented, remove the ending accent. This may be too simple.
elseif match(stem, export.accent) and match(ending, export.accent) then
ending = gsub(ending, export.accent, "")
end
end
return stem .. ending
end
--[=[Return a word-stem combined with a given ending while handling internal
sandhi and accentuation. Please see the implementation for details.
Parameters:
input_table (Table): This table is expected to contain the items:
stem (String): the stem to receive an ending
ending (String): the ending to be affixed
has_accent (Boolean): whether the word has an accent to be modified
mono (Boolean): whether the stem is monosyllabic OR behaves like a monosyllable (e.g. root noun compounds)
accent_override (Boolean): whether to strip the stem of accent since
some non-monosyllabic forms (e.g. present participles and gen.pl.)
may show stem-to-ending accentual mobility.
recessive (Boolean): whether the accent must be moved to the leftmost vowel (e.g. in the vocative)
j_to_z (Boolean): whether to convert j > ṣ before {t, th} instead of j > k
h_to_g (Boolean): whether to convert h > g before {t, th, d, dh} (duh + -tá = dugdhá) instead of h + t > ḍh (lih + -tá = līḍhá)
non_final (Boolean): if true, will not apply word-final sandhi (i.e. convert s to visarga)
ignore_s_allophones (Boolean): whether to ignore r and s allophony in the stem before the ending
Return:
String
]=]
function export.internal_sandhi(input_table)
local stem, ending = input_table.stem, input_table.ending
local last -- last segment of the stem
local acc -- the accent
local first -- the first segment of the ending
local combined -- the combined form
-- explicitly ignored are CV, C + semivowel, or C + nasal
if ending == "" then
return absolute_final(stem, input_table.ambig_hint)
-- all cases of ending starts with vowel
elseif starts_with(ending, export.vowel) then
if ends_with(stem, export.vowel_with_accent) then -- stem ends with vowel
-- strip last vowel and accent off stem
stem, last, acc = match(stem, "^(.*)(" .. export.vowel .. ")(" .. export.accent .. "?)$")
-- strip first vowel off ending
first, ending = match(ending, "^(.)(.*)$")
if match(last, '[iIuU]') and input_table.mono then -- monosyllabic semivowel-final stems (this applies to root noun compounds as well)
stem = stem .. insert_glide[last .. acc]
ending = first .. ending
elseif lower(last) == lower(first) then -- homorganic vowels (FIXME: what happens if e- + -e, o- + -o, E- + -E, O- + -O?)
ending = upper(first) .. acc .. ending
elseif lower(last) == "a" then -- gunation and vrddhization after stem-final a.
ending = export.up_one_grade[first .. acc] .. ending
elseif export.semivowel_to_cons[last] then -- Can the stem-final vowel be made consonantal?
stem = stem .. export.semivowel_to_cons[last]
ending = first .. (acc == "/" and "\\" or "") .. ending -- Convert stem-final uditta to ending-initial svarita
elseif export.split_diphthong[last] then -- Can a stem-final guna and vrddhi be split into V + sonorant?
stem = stem .. export.split_diphthong[last .. acc]
ending = first .. ending
end
end
-- all consonant-final stems left unchanged
-- {i, u} > {ī, ū} /__[rv]C if stem is monosyllabic (is monosyllabic constraint necessary)
elseif ends_with(stem, "[iu][/\\]?[rv]") and input_table.mono then
-- lengthen high vowel before [rv]].
stem = gsub(stem, "([iu][/\\]?)([rv])$", function(vow, sonorant) return export.lengthen[vow] .. sonorant end)
-- n > ñ /__{c, j}
elseif ends_with(stem, "[cj]") and starts_with(ending, "n") then
ending = gsub(ending, "^.", "Y")
-- ś > k /__s (RUKI applied later)
elseif ends_with(stem, "S") and starts_with(ending, "s") then
stem = gsub(stem, ".$", "k")
-- s > t /__s if stem is monosyllabic
elseif ends_with(stem, "s") and starts_with(ending, "s") and input_table.mono then
stem = gsub(stem, ".$", "t")
-- bh > d /__s if stem is monosyllabic (FIXME: probably only be in (some) nominals)
elseif ends_with(stem, "s") and starts_with(ending, "B") and input_table.mono then
stem = gsub(stem, ".$", "d")
-- j > ṣ /__{t, th} in certain words (FIXME: does this get handled correctly if j_to_z is false?)
elseif ends_with(stem, "j") and starts_with(ending, "[tT]") and input_table.j_to_z then
stem = gsub(stem, ".$", "z")
-- {a, i, u}h + {t, th, d, dh} > {ā, ī, ū}ḍh (Bartholomae's Law with retroflection and compensatory lengthening)
elseif ends_with(stem, "h") and starts_with(ending, "[tTdD]") then
if input_table.h_to_g then
stem = gsub(stem, ".$", "g")
ending = gsub(ending, "^.", "D")
else
stem = gsub(stem, "([aiu]?)([/\\]?)h$", function(vow, acc) return (export.lengthen[vow] or "") .. acc end)
ending = gsub(ending, "[tTdD]", "Q")
end
elseif ends_with(stem, "h") and starts_with(ending, "s") then
stem = gsub(stem, ".$", "k")
ending = gsub(ending, "^.", "z")
-- Bartholomae's Law
elseif ends_with(stem, "[GJQDBh]") and starts_with(ending, "[tT]") then
stem = gsub(stem, ".$", deaspirate)
ending = gsub(ending, "^.", "D")
-- Allo other C- + -C interactions
elseif ends_with(stem, export.consonant) and starts_with(ending, export.consonant) then
if input_table.final then -- (FIXME: I don't recall what this parameter is for. When would this be called?)
if ends_with(stem, export.consonant .. export.consonant) then -- at least 2 consonants
-- take the first of the cluster
stem = gsub(stem, "(" .. export.consonant .. "+)$",
function(cluster) return sub(cluster, 1, 1) end)
end
if ends_with(stem, "[KgGWqQTdDPbB]") then
stem = gsub(stem, ".$", to_final)
elseif ends_with(stem, "[cCjJhSz]") then
stem = gsub(stem, ".$", input_table.ambig_hint)
end
end
if ends_with(stem, "[cCjJ]") and starts_with(ending, "[tTdDs]") then
if ends_with(stem, "Y[cCjJ]") then
stem = gsub(stem, "..$", 'Nk')
else
stem = gsub(stem, ".$", 'k')
end
end
if ends_with(stem, "[kwp]") then -- if stem ends in {k, ṭ, p}
if starts_with(ending, "[gGjJqQdDbB]") then -- {k, ṭ, p} > {g, ḍ, b} before following voiced stop
stem = gsub(stem, ".$", {['k'] = 'g', ['w'] = 'q', ['p'] = 'b'})
elseif starts_with(ending, "h") then -- {k, ṭ, p}h > {ggh, ḍḍh, bbh}
stem = gsub(stem, ".$", {['k'] = 'g', ['w'] = 'q', ['p'] = 'b'})
ending = gsub(ending, "^.", gsub(stem, ".$", {['k'] = 'G', ['w'] = 'Q', ['p'] = 'B'}))
end
elseif ends_with(stem, "[gqbd]") then -- if stem ends in {g, ḍ, b}
if starts_with(ending, "[kKcCwWtTpP]") then -- {g, ḍ, d, b} > {k, ṭ, t, p} before following unvoiced stop
stem = gsub(stem, ".$", {['g'] = 'k', ['q'] = 'w', ['d'] = 't', ['b'] = 'p'})
end
elseif ends_with(stem, "t") then -- if stem ends in t
if starts_with(ending, "[cCjJwWqQ]") then -- homorganic with following stop
stem = gsub(stem, ".$", gsub(ending, "^.",
{
['c'] = 'c', ['C'] = 'c', ['j'] = 'j', ['J'] = 'J',
['w'] = 'w', ['W'] = 'w', ['q'] = 'q', ['Q'] = 'q',
}))
elseif starts_with(ending, "S") then -- tś > cch
stem = gsub(stem, ".$", "c")
ending = gsub(ending, "^.", "C")
elseif starts_with(ending, "[gGdDbB]") then -- t > d /__{g(h), d(h), b(h)}
stem = gsub(stem, ".$", "d")
elseif starts_with(ending, "[nm]") then -- t > n /__{n, m}
stem = gsub(stem, ".$", "n")
elseif starts_with(ending, "h") then -- t + h > ddh
stem = gsub(stem, ".$", "d")
ending = gsub(ending, "^.", "D")
end
elseif ends_with(stem, "m") then -- if stem ends in m
if starts_with(ending, "[hSzs]") then -- m > ṃ /__{h, ś, ṣ, s}
stem = gsub(stem, ".$", "M")
elseif starts_with(ending, "[^yrln]") then -- m > n before any other consonant beside {y, r, l, n} (FIXME: Is this true? Should this feed into the next conditional?)
stem = gsub(stem, ".$", "n")
end
elseif ends_with(stem, "n") then -- if stem ends in n
if starts_with(ending, "[hSzs]") then -- n > ṃ /__{h, ś, ṣ, s}
stem = gsub(stem, ".$", "M")
elseif starts_with(ending, "[kKgGcCjJwWqQpPbBl]") then -- make homorganic
stem = gsub(stem, ".$",
{
['k'] = 'N', ['K'] = 'N', ['g'] = 'N', ['G'] = 'N',
['c'] = 'Y', ['C'] = 'Y', ['j'] = 'Y', ['J'] = 'Y',
['w'] = 'R', ['W'] = 'R', ['q'] = 'R', ['Q'] = 'R',
['p'] = 'm', ['P'] = 'm', ['b'] = 'm', ['B'] = 'm',
['l'] = 'M', -- or 'l~'
})
end
-- Loss of {z, ẓ} with compensatory lengthening before voiced consonant. (FIXME: but what about the médha- < *mázdha- type?)
elseif ends_with(stem, "[aA][/\\]?[sHr]") and starts_with(ending, "[rgGdDbByvjJqQlLhnm]") and (not input_table.ignore_s_allophones) then
stem = gsub(stem, "([aA])([/\\]?)[sHr]$",
function(vow, acc) return (vow == "a" and "o" or "A") .. acc end)
-- final s-allophones
elseif ends_with(stem, "[sHr]") and (not input_table.ignore_s_allophones) then
if starts_with(ending, "[kKpPzsS]") then -- visarga
stem = gsub(stem, ".$", "H")
elseif starts_with(ending, "[cCwWtT]") then -- homorganic fricative
local homorg_s = {
['c'] = 'S', ['C'] = 'S',
['w'] = 'z', ['W'] = 'Z',
['t'] = 's', ['T'] = 's'
}
stem = gsub(stem, ".$", homorg_s[sub(ending, 1, 1)])
elseif starts_with(ending, "r") then -- Loss of z before r with compensatory lengthening before voiced consonant. (FIXME: Redundant/correct?)
stem = gsub(stem, "(" .. export.vowel .. "[/\\])[sHr]$", function(vow) return export.lengthen[vow] or vow end)
elseif starts_with(ending, "[gGjJqQdDbByvlLhnm]") then -- s-allophones > r (FIXME: Redundant/correct?)
stem = gsub(stem, ".$", "r")
end
elseif ends_with(stem, export.consonant .. "r") then -- Final Cr > Cṛ if the ending begins with a consonant
stem = gsub(stem, "r$", "f")
end
end
stem, ending = export.retroflexion(stem, ending)
combined = combine_accent(stem, ending, input_table.has_accent, input_table.accent_override, input_table.mono, input_table.recessive)
if input_table.non_final then return combined end
return absolute_final(combined, input_table.ambig_hint)
end
return export
