diff options
Diffstat (limited to 'tex/context/base/mkiv/l-string.lua')
| -rw-r--r-- | tex/context/base/mkiv/l-string.lua | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/tex/context/base/mkiv/l-string.lua b/tex/context/base/mkiv/l-string.lua new file mode 100644 index 000000000..e9dc2bbbc --- /dev/null +++ b/tex/context/base/mkiv/l-string.lua @@ -0,0 +1,213 @@ +if not modules then modules = { } end modules ['l-string'] = { + version = 1.001, + comment = "companion to luat-lib.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +local string = string +local sub, gmatch, format, char, byte, rep, lower = string.sub, string.gmatch, string.format, string.char, string.byte, string.rep, string.lower +local lpegmatch, patterns = lpeg.match, lpeg.patterns +local P, S, C, Ct, Cc, Cs = lpeg.P, lpeg.S, lpeg.C, lpeg.Ct, lpeg.Cc, lpeg.Cs + +-- Some functions are already defined in l-lpeg and maybe some from here will +-- move there (unless we also expose caches). + +-- if not string.split then +-- +-- function string.split(str,pattern) +-- local t = { } +-- if #str > 0 then +-- local n = 1 +-- for s in gmatch(str..pattern,"(.-)"..pattern) do +-- t[n] = s +-- n = n + 1 +-- end +-- end +-- return t +-- end +-- +-- end + +-- function string.unquoted(str) +-- return (gsub(str,"^([\"\'])(.*)%1$","%2")) -- interesting pattern +-- end + +local unquoted = patterns.squote * C(patterns.nosquote) * patterns.squote + + patterns.dquote * C(patterns.nodquote) * patterns.dquote + +function string.unquoted(str) + return lpegmatch(unquoted,str) or str +end + +-- print(string.unquoted("test")) +-- print(string.unquoted([["t\"est"]])) +-- print(string.unquoted([["t\"est"x]])) +-- print(string.unquoted("\'test\'")) +-- print(string.unquoted('"test"')) +-- print(string.unquoted('"test"')) + +function string.quoted(str) + return format("%q",str) -- always double quote +end + +function string.count(str,pattern) -- variant 3 + local n = 0 + for _ in gmatch(str,pattern) do -- not for utf + n = n + 1 + end + return n +end + +function string.limit(str,n,sentinel) -- not utf proof + if #str > n then + sentinel = sentinel or "..." + return sub(str,1,(n-#sentinel)) .. sentinel + else + return str + end +end + +local stripper = patterns.stripper +local fullstripper = patterns.fullstripper +local collapser = patterns.collapser +local longtostring = patterns.longtostring + +function string.strip(str) + return lpegmatch(stripper,str) or "" +end + +function string.fullstrip(str) + return lpegmatch(fullstripper,str) or "" +end + +function string.collapsespaces(str) + return lpegmatch(collapser,str) or "" +end + +function string.longtostring(str) + return lpegmatch(longtostring,str) or "" +end + +-- function string.is_empty(str) +-- return not find(str,"%S") +-- end + +local pattern = P(" ")^0 * P(-1) -- maybe also newlines + +-- patterns.onlyspaces = pattern + +function string.is_empty(str) + if str == "" then + return true + else + return lpegmatch(pattern,str) and true or false + end +end + +-- if not string.escapedpattern then +-- +-- local patterns_escapes = { +-- ["%"] = "%%", +-- ["."] = "%.", +-- ["+"] = "%+", ["-"] = "%-", ["*"] = "%*", +-- ["["] = "%[", ["]"] = "%]", +-- ["("] = "%(", [")"] = "%)", +-- -- ["{"] = "%{", ["}"] = "%}" +-- -- ["^"] = "%^", ["$"] = "%$", +-- } +-- +-- local simple_escapes = { +-- ["-"] = "%-", +-- ["."] = "%.", +-- ["?"] = ".", +-- ["*"] = ".*", +-- } +-- +-- function string.escapedpattern(str,simple) +-- return (gsub(str,".",simple and simple_escapes or patterns_escapes)) +-- end +-- +-- function string.topattern(str,lowercase,strict) +-- if str == "" then +-- return ".*" +-- else +-- str = gsub(str,".",simple_escapes) +-- if lowercase then +-- str = lower(str) +-- end +-- if strict then +-- return "^" .. str .. "$" +-- else +-- return str +-- end +-- end +-- end +-- +-- end + +--- needs checking + +local anything = patterns.anything +local allescapes = Cc("%") * S(".-+%?()[]*") -- also {} and ^$ ? +local someescapes = Cc("%") * S(".-+%()[]") -- also {} and ^$ ? +local matchescapes = Cc(".") * S("*?") -- wildcard and single match + +local pattern_a = Cs ( ( allescapes + anything )^0 ) +local pattern_b = Cs ( ( someescapes + matchescapes + anything )^0 ) +local pattern_c = Cs ( Cc("^") * ( someescapes + matchescapes + anything )^0 * Cc("$") ) + +function string.escapedpattern(str,simple) + return lpegmatch(simple and pattern_b or pattern_a,str) +end + +function string.topattern(str,lowercase,strict) + if str=="" or type(str) ~= "string" then + return ".*" + elseif strict then + str = lpegmatch(pattern_c,str) + else + str = lpegmatch(pattern_b,str) + end + if lowercase then + return lower(str) + else + return str + end +end + +-- print(string.escapedpattern("12+34*.tex",false)) +-- print(string.escapedpattern("12+34*.tex",true)) +-- print(string.topattern ("12+34*.tex",false,false)) +-- print(string.topattern ("12+34*.tex",false,true)) + +function string.valid(str,default) + return (type(str) == "string" and str ~= "" and str) or default or nil +end + +-- handy fallback + +string.itself = function(s) return s end + +-- also handy (see utf variant) + +local pattern_c = Ct( C(1) ^0) -- string and not utf ! +local pattern_b = Ct((C(1)/byte)^0) + +function string.totable(str,bytes) + return lpegmatch(bytes and pattern_b or pattern_c,str) +end + +-- handy from within tex: + +local replacer = lpeg.replacer("@","%%") -- Watch the escaped % in lpeg! + +function string.tformat(fmt,...) + return format(lpegmatch(replacer,fmt),...) +end + +-- obsolete names: + +string.quote = string.quoted +string.unquote = string.unquoted |