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--[[
Copyright 2016 ARATA Mizuki
This file is part of ClutTeX.
ClutTeX is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
ClutTeX is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with ClutTeX. If not, see <http://www.gnu.org/licenses/>.
]]
local assert = assert
local string_match = string.match
local table = table
local table_insert = table.insert
local table_concat = table.concat
-- s: string
local function escape(s)
local len = #s
local result = {}
local t,i = string_match(s, "^([^']*)()")
assert(t)
if t ~= "" then
table_insert(result, "'")
table_insert(result, t)
table_insert(result, "'")
end
while i < len do
t,i = string_match(s, "^('+)()", i)
assert(t)
table_insert(result, '"')
table_insert(result, t)
table_insert(result, '"')
t,i = string_match(s, "^([^']*)()", i)
assert(t)
if t ~= "" then
table_insert(result, "'")
table_insert(result, t)
table_insert(result, "'")
end
end
return table_concat(result, "")
end
-- TEST CODE
assert(escape([[Hello world!]]) == [['Hello world!']])
assert(escape([[Hello' world!]]) == [['Hello'"'"' world!']])
assert(escape([[Hello' world!"]]) == [['Hello'"'"' world!"']])
-- END TEST CODE
return {
escape = escape,
}
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