diff options
| -rw-r--r-- | lualibs-string.lua | 285 |
1 files changed, 66 insertions, 219 deletions
diff --git a/lualibs-string.lua b/lualibs-string.lua index 9856d52..03616aa 100644 --- a/lualibs-string.lua +++ b/lualibs-string.lua @@ -6,8 +6,9 @@ if not modules then modules = { } end modules ['l-string'] = { license = "see context related readme files" } +local string = string local sub, gsub, find, match, gmatch, format, char, byte, rep, lower = string.sub, string.gsub, string.find, string.match, string.gmatch, string.format, string.char, string.byte, string.rep, string.lower -local lpegmatch = lpeg.match +local lpegmatch, S, C, Ct = lpeg.match, lpeg.S, lpeg.C, lpeg.Ct -- some functions may disappear as they are not used anywhere @@ -15,196 +16,75 @@ if not string.split then -- this will be overloaded by a faster lpeg variant - function string:split(pattern) - if #self > 0 then - local t = { } - for s in gmatch(self..pattern,"(.-)"..pattern) do - t[#t+1] = s + 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 - return t - else - return { } end + return t end end -local chr_to_esc = { - ["%"] = "%%", - ["."] = "%.", - ["+"] = "%+", ["-"] = "%-", ["*"] = "%*", - ["^"] = "%^", ["$"] = "%$", - ["["] = "%[", ["]"] = "%]", - ["("] = "%(", [")"] = "%)", - ["{"] = "%{", ["}"] = "%}" -} - -string.chr_to_esc = chr_to_esc - -function string:esc() -- variant 2 - return (gsub(self,"(.)",chr_to_esc)) -end - -function string:unquote() - return (gsub(self,"^([\"\'])(.*)%1$","%2")) +function string.unquoted(str) + return (gsub(str,"^([\"\'])(.*)%1$","%2")) end ---~ function string:unquote() ---~ if find(self,"^[\'\"]") then ---~ return sub(self,2,-2) +--~ function stringunquoted(str) +--~ if find(str,"^[\'\"]") then +--~ return sub(str,2,-2) --~ else ---~ return self +--~ return str --~ end --~ end -function string:quote() -- we could use format("%q") - return format("%q",self) +function string.quoted(str) + return format("%q",str) -- always " end -function string:count(pattern) -- variant 3 +function string.count(str,pattern) -- variant 3 local n = 0 - for _ in gmatch(self,pattern) do + for _ in gmatch(str,pattern) do -- not for utf n = n + 1 end return n end -function string:limit(n,sentinel) - if #self > n then - sentinel = sentinel or " ..." - return sub(self,1,(n-#sentinel)) .. sentinel +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 self + return str end end ---~ function string:strip() -- the .- is quite efficient ---~ -- return match(self,"^%s*(.-)%s*$") or "" ---~ -- return match(self,'^%s*(.*%S)') or '' -- posted on lua list ---~ return find(s,'^%s*$') and '' or match(s,'^%s*(.*%S)') ---~ end - -do -- roberto's variant: - local space = lpeg.S(" \t\v\n") - local nospace = 1 - space - local stripper = space^0 * lpeg.C((space^0 * nospace^1)^0) - function string.strip(str) - return lpegmatch(stripper,str) or "" - end -end +local space = S(" \t\v\n") +local nospace = 1 - space +local stripper = space^0 * C((space^0 * nospace^1)^0) -- roberto's code -function string:is_empty() - return not find(self,"%S") +function string.strip(str) + return lpegmatch(stripper,str) or "" end -function string:enhance(pattern,action) - local ok, n = true, 0 - while ok do - ok = false - self = gsub(self,pattern, function(...) - ok, n = true, n + 1 - return action(...) - end) - end - return self, n -end - -local chr_to_hex, hex_to_chr = { }, { } - -for i=0,255 do - local c, h = char(i), format("%02X",i) - chr_to_hex[c], hex_to_chr[h] = h, c -end - -function string:to_hex() - return (gsub(self or "","(.)",chr_to_hex)) -end - -function string:from_hex() - return (gsub(self or "","(..)",hex_to_chr)) -end - -if not string.characters then - - local function nextchar(str, index) - index = index + 1 - return (index <= #str) and index or nil, sub(str,index,index) - end - function string:characters() - return nextchar, self, 0 - end - local function nextbyte(str, index) - index = index + 1 - return (index <= #str) and index or nil, byte(sub(str,index,index)) - end - function string:bytes() - return nextbyte, self, 0 - end - -end - --- we can use format for this (neg n) - -function string:rpadd(n,chr) - local m = n-#self - if m > 0 then - return self .. rep(chr or " ",m) - else - return self - end -end - -function string:lpadd(n,chr) - local m = n-#self - if m > 0 then - return rep(chr or " ",m) .. self - else - return self - end -end - -string.padd = string.rpadd - -function is_number(str) -- tonumber - return find(str,"^[%-%+]?[%d]-%.?[%d+]$") == 1 -end - ---~ print(is_number("1")) ---~ print(is_number("1.1")) ---~ print(is_number(".1")) ---~ print(is_number("-0.1")) ---~ print(is_number("+0.1")) ---~ print(is_number("-.1")) ---~ print(is_number("+.1")) - -function string:split_settings() -- no {} handling, see l-aux for lpeg variant - if find(self,"=") then - local t = { } - for k,v in gmatch(self,"(%a+)=([^%,]*)") do - t[k] = v - end - return t - else - return nil - end +function string.is_empty(str) + return not find(str,"%S") end local patterns_escapes = { - ["-"] = "%-", - ["."] = "%.", - ["+"] = "%+", - ["*"] = "%*", ["%"] = "%%", - ["("] = "%)", - [")"] = "%)", - ["["] = "%[", - ["]"] = "%]", + ["."] = "%.", + ["+"] = "%+", ["-"] = "%-", ["*"] = "%*", + ["["] = "%[", ["]"] = "%]", + ["("] = "%(", [")"] = "%)", + -- ["{"] = "%{", ["}"] = "%}" + -- ["^"] = "%^", ["$"] = "%$", } -function string:pattesc() - return (gsub(self,".",patterns_escapes)) -end - local simple_escapes = { ["-"] = "%-", ["."] = "%.", @@ -212,77 +92,44 @@ local simple_escapes = { ["*"] = ".*", } -function string:simpleesc() - return (gsub(self,".",simple_escapes)) +function string.escapedpattern(str,simple) + return (gsub(str,".",simple and simple_escapes or patterns_escapes)) end -function string:tohash() - local t = { } - for s in gmatch(self,"([^, ]+)") do -- lpeg - t[s] = true +function string.topattern(str,lowercase,strict) + if str == "" then + return ".*" + else + str = gsub(str,".",simple_escapes) + if lowercase then + str = lower(str) + end + if strict then + return "^" .. str .. "$" + else + return str + end end - return t end -local pattern = lpeg.Ct(lpeg.C(1)^0) -function string:totable() - return lpegmatch(pattern,self) +function string.valid(str,default) + return (type(str) == "string" and str ~= "" and str) or default or nil end ---~ local t = { ---~ "1234567123456712345671234567", ---~ "a\tb\tc", ---~ "aa\tbb\tcc", ---~ "aaa\tbbb\tccc", ---~ "aaaa\tbbbb\tcccc", ---~ "aaaaa\tbbbbb\tccccc", ---~ "aaaaaa\tbbbbbb\tcccccc", ---~ } ---~ for k,v do ---~ print(string.tabtospace(t[k])) ---~ end +-- obsolete names: -function string.tabtospace(str,tab) - -- we don't handle embedded newlines - while true do - local s = find(str,"\t") - if s then - if not tab then tab = 7 end -- only when found - local d = tab-(s-1) % tab - if d > 0 then - str = gsub(str,"\t",rep(" ",d),1) - else - str = gsub(str,"\t","",1) - end - else - break - end - end - return str -end +string.quote = string.quoted +string.unquote = string.unquoted -function string:compactlong() -- strips newlines and leading spaces - self = gsub(self,"[\n\r]+ *","") - self = gsub(self,"^ *","") - return self -end +-- handy fallback -function string:striplong() -- strips newlines and leading spaces - self = gsub(self,"^%s*","") - self = gsub(self,"[\n\r]+ *","\n") - return self -end +string.itself = function(s) return s end -function string:topattern(lowercase,strict) - if lowercase then - self = lower(self) - end - self = gsub(self,".",simple_escapes) - if self == "" then - self = ".*" - elseif strict then - self = "^" .. self .. "$" - end - return self +-- also handy (see utf variant) + +local pattern = Ct(C(1)^0) + +function string.totable(str) + return lpegmatch(pattern,str) end |