Module:Sandbox/trappist the monk/math explained

require('strict');-- $3987^\; +\; 4365^\; =\; 4472^$local function math_test (frame) local math_title = frame.args['math-title']; if math_title:find ('\127[^\127]*UNIQ%-%-math%-[%a%d]+%-QINU[^\127]*\127') then return '

math-title has ... markup'; end local math_t = ; -- temporary holding spot for math strip markers local escaped = '__35c4p3d__'; -- the special secret EScApEd keyword local str = math_title:gsub ('\\%$', escaped); -- replace '\$' (escaped $) with special secret EScApEd keyword

local count; str, count = str:gsub ('%$', '%1'); -- there must be $-delimited text and the delimters must be balanced if 0

count then return '

|math-title= missing TeX delimiters'; elseif 0 ~= count % 2 then return '|math-title= has unbalanced TeX delimiters'; end local pattern = '(%$([^%$]+)%$)'; -- pattern used to find $-delimited math text for math_str in str:gmatch (pattern) do -- walk through the text and for each $-delimited math text math_str = math_str:gsub (pattern, '$\%2$'); -- replace the delimiters math_str = math_str:gsub (escaped, '\\%$'); -- replace special secret EScApEd keyword with '\$' math_str = frame:preprocess (math_str); -- preprocess math text into a math strip marker table.insert (math_t, math_str); -- and save the math strip marker end

for _, stripmarker in ipairs (math_t) do str = str:gsub (pattern, stripmarker, 1); -- replace $-delimited math text with matching strip marker end str = str:gsub (escaped, '%$'); -- replace special secret EScApEd keyword with unescaped form '$' return table.concat ;end

local function math_test2 (frame) local math_title = frame.args['math-title']; if math_title:find ('\127[^\127]*UNIQ%-%-math%-[%a%d]+%-QINU[^\127]*\127') then return '

math-title has ... markup'; end local math_t = ; -- temporary holding spot for math strip markers local str = math_title; local pattern = '(\\%((.-)\\%))'; -- pattern used to find \(...\) delimited math text

if not str:find (pattern) then -- there must be \(...\) delimited text and the delimters must be balanced return '

|math-title= missing TeX delimiters'; end

for math_str in str:gmatch (pattern) do -- walk through the text and for each \(...\) delimited math text math_str = math_str:gsub (pattern, '$\%2$'); -- replace the delimiters math_str = frame:preprocess (math_str); -- preprocess math text into a math strip marker table.insert (math_t, math_str); -- and save the math strip marker end

for _, stripmarker in ipairs (math_t) do str = str:gsub (pattern, stripmarker, 1); -- replace \(...\) delimited math text with matching strip marker end

return table.concat ;end

local function span_test (frame) local span_str = frame.args[1]; local patterns_t = for _, pattern_t in ipairs (patterns_t) do span_str = span_str:gsub (pattern_t[1], pattern_t[2]); end

local count = 1; while 0 ~= count do span_str, count = span_str:gsub ('

(.-)', '%1'); end

return span_str;end

return