Re: [NTG-context] Solved: Minimum example of problem getting curly braces printed in METAPOST

5 Apr 2020


      On 4/3/2020 5:36 PM, Gerben Wierda wrote:
...
Thanks to Taco, the solution was to simply use:
function doubleQuotableEscapedConTeXtString( str)
   local rep = {
       [1] =  { '{', '{\\textbraceleft}' },
       [2] =  { '}', '{\\textbraceright}' },
       [3] =  { '#', '{\\texthash}' },
       [4] =  { '$', '{\\textdollar}' },
       [5] =  { '&', '{\\textampersand}' },
       [6] =  { '%', '{\\textpercent}' },
       [7] =  { '\\','{\\textbackslash}' },
       [8] =  { '|', '{\\textbar}' },
       [9] =  { '_', '{\\textunderscore}' },
       [10] = { '~', '{\\textasciitilde}' },
       [11] = { '^', '{\\textasciicircum}' },
       [12] = { '"', "\"&ditto&\"" },
   }
   return lpeg.replacer(rep):match(str)
end
And the string becomes something that can safely be given toi METAPOST 
and safely handled by TeX when called from METAPOST via textext()
more efficient
local rep = lpeg.replacer {
   { '{', '{\\textbraceleft}' },
   { '}', '{\\textbraceright}' },
   { '#', '{\\texthash}' },
   { '$', '{\\textdollar}' },
   { '&', '{\\textampersand}' },
   { '%', '{\\textpercent}' },
   { '\\','{\\textbackslash}' },
   { '|', '{\\textbar}' },
   { '_', '{\\textunderscore}' },
   { '~', '{\\textasciitilde}' },
   { '^', '{\\textasciicircum}' },
   { '"', "\"&ditto&\"" },
}

function doubleQuotableEscapedConTeXtString( str)
     return rep:match(str)
end

this is probably also ok:

local rep = {
     ["\""] = "\\char34 ",
     ["#"]  = "\\char35 ",
     ["$"]  = "\\char36 ",
     ["%"]  = "\\char37 ",
     ["&"]  = "\\char38 ",
     ["\\"] = "\\char92 ",
     ["^"]  = "\\char94 ",
     ["_"]  = "\\char95 ",
     ["{"]  = "\\char123 ",
     ["|"]  = "\\char124 ",
     ["}"]  = "\\char125 ",
     ["~"]  = "\\char126 ",
}

function doubleQuotableEscapedConTeXtString(str)
     return (string.gsub(str,".",rep))
end


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