if not modules then modules = { } end modules ['util-tpl'] = {
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"
}
-- This is experimental code. Coming from dos and windows, I've always used %whatever%
-- as template variables so let's stick to it. After all, it's easy to parse and stands
-- out well. A double %% is turned into a regular %.
utilities.templates = utilities.templates or { }
local templates = utilities.templates
local trace_template = false trackers.register("templates.trace",function(v) trace_template = v end)
local report_template = logs.reporter("template")
local tostring, next = tostring, next
local format, sub, byte = string.format, string.sub, string.byte
local P, C, R, Cs, Cc, Carg, lpegmatch, lpegpatterns = lpeg.P, lpeg.C, lpeg.R, lpeg.Cs, lpeg.Cc, lpeg.Carg, lpeg.match, lpeg.patterns
local formatters = string.formatters
-- todo: make installable template.new
local replacer
local function replacekey(k,t,how,recursive)
local v = t[k]
if not v then
if trace_template then
report_template("unknown key %a",k)
end
return ""
else
v = tostring(v)
if trace_template then
report_template("setting key %a to value %a",k,v)
end
if recursive then
return lpegmatch(replacer,v,1,t,how,recursive)
else
return v
end
end
end
local sqlescape = lpeg.replacer {
{ "'", "''" },
{ "\\", "\\\\" },
{ "\r\n", "\\n" },
{ "\r", "\\n" },
-- { "\t", "\\t" },
}
local sqlquoted = Cs(Cc("'") * sqlescape * Cc("'"))
lpegpatterns.sqlescape = sqlescape
lpegpatterns.sqlquoted = sqlquoted
-- escapeset : \0\1\2\3\4\5\6\7\8\9\10\11\12\13\14\15\16\17\18\19\20\21\22\23\24\25\26\27\28\29\30\31\"\\\127
-- test string: [[1\0\31test23"\\]] .. string.char(19) .. "23"
--
-- slow:
--
-- local luaescape = lpeg.replacer {
-- { '"', [[\"]] },
-- { '\\', [[\\]] },
-- { R("\0\9") * #R("09"), function(s) return "\\00" .. byte(s) end },
-- { R("\10\31") * #R("09"), function(s) return "\\0" .. byte(s) end },
-- { R("\0\31") , function(s) return "\\" .. byte(s) end },
-- }
--
-- slightly faster:
-- local luaescape = Cs ((
-- P('"' ) / [[\"]] +
-- P('\\') / [[\\]] +
-- Cc("\\00") * (R("\0\9") / byte) * #R("09") +
-- Cc("\\0") * (R("\10\31") / byte) * #R("09") +
-- Cc("\\") * (R("\0\31") / byte) +
-- P(1)
-- )^0)
----- xmlescape = lpegpatterns.xmlescape
----- texescape = lpegpatterns.texescape
local luaescape = lpegpatterns.luaescape
----- sqlquoted = lpegpatterns.sqlquoted
----- luaquoted = lpegpatterns.luaquoted
local escapers = {
lua = function(s)
-- return sub(format("%q",s),2,-2)
return lpegmatch(luaescape,s)
end,
sql = function(s)
return lpegmatch(sqlescape,s)
end,
}
local quotedescapers = {
lua = function(s)
-- return lpegmatch(luaquoted,s)
return format("%q",s)
end,
sql = function(s)
return lpegmatch(sqlquoted,s)
end,
}
local luaescaper = escapers.lua
local quotedluaescaper = quotedescapers.lua
local function replacekeyunquoted(s,t,how,recurse) -- ".. \" "
if how == false then
return replacekey(s,t,how,recurse)
else
local escaper = how and escapers[how] or luaescaper
return escaper(replacekey(s,t,how,recurse))
end
end
local function replacekeyquoted(s,t,how,recurse) -- ".. \" "
if how == false then
return replacekey(s,t,how,recurse)
else
local escaper = how and quotedescapers[how] or quotedluaescaper
return escaper(replacekey(s,t,how,recurse))
end
end
local function replaceoptional(l,m,r,t,how,recurse)
local v = t[l]
return v and v ~= "" and lpegmatch(replacer,r,1,t,how or "lua",recurse or false) or ""
end
local function replaceformatted(l,m,r,t,how,recurse)
local v = t[r]
return v and formatters[l](v)
end
local single = P("%") -- test %test% test : resolves test
local double = P("%%") -- test 10%% test : %% becomes %
local lquoted = P("%[") -- test '%[test]%' test : resolves to test with escaped "'s
local rquoted = P("]%") --
local lquotedq = P("%(") -- test %(test)% test : resolves to 'test' with escaped "'s
local rquotedq = P(")%") --
local escape = double / '%%'
local nosingle = single / ''
local nodouble = double / ''
local nolquoted = lquoted / ''
local norquoted = rquoted / ''
local nolquotedq = lquotedq / ''
local norquotedq = rquotedq / ''
local nolformatted = P(":") / "%%"
local norformatted = P(":") / ""
local noloptional = P("%?") / ''
local noroptional = P("?%") / ''
local nomoptional = P(":") / ''
local args = Carg(1) * Carg(2) * Carg(3)
local key = nosingle * ((C((1-nosingle)^1) * args) / replacekey) * nosingle
local quoted = nolquotedq * ((C((1-norquotedq)^1) * args) / replacekeyquoted) * norquotedq
local unquoted = nolquoted * ((C((1-norquoted)^1) * args) / replacekeyunquoted) * norquoted
local optional = noloptional * ((C((1-nomoptional)^1) * nomoptional * C((1-noroptional)^1) * args) / replaceoptional) * noroptional
local formatted = nosingle * ((Cs(nolformatted * (1-norformatted )^1) * norformatted * C((1-nosingle)^1) * args) / replaceformatted) * nosingle
local any = P(1)
replacer = Cs((unquoted + quoted + formatted + escape + optional + key + any)^0)
local function replace(str,mapping,how,recurse)
if mapping and str then
return lpegmatch(replacer,str,1,mapping,how or "lua",recurse or false) or str
else
return str
end
end
-- print(replace("test '%[x]%' test",{ x = [[a 'x' a]] }))
-- print(replace("test '%x%' test",{ x = [[a "x" a]] }))
-- print(replace([[test "%[x]%" test]],{ x = [[a "x" a]] }))
-- print(replace("test '%[x]%' test",{ x = true }))
-- print(replace("test '%[x]%' test",{ x = [[a 'x' a]], y = "oeps" },'sql'))
-- print(replace("test '%[x]%' test",{ x = [[a '%y%' a]], y = "oeps" },'sql',true))
-- print(replace([[test %[x]% test]],{ x = [[a "x" a]]}))
-- print(replace([[test %(x)% test]],{ x = [[a "x" a]]}))
-- print(replace([[convert %?x: -x "%x%" ?% %?y: -y "%y%" ?%]],{ x = "yes" }))
-- print(replace("test %:0.3N:x% test",{ x = 123.45 }))
-- print(replace("test %:0.3N:x% test",{ x = 12345 }))
templates.replace = replace
function templates.replacer(str,how,recurse) -- reads nicer
return function(mapping)
return lpegmatch(replacer,str,1,mapping,how or "lua",recurse or false) or str
end
end
-- local cmd = templates.replacer([[foo %bar%]]) print(cmd { bar = "foo" })
function templates.load(filename,mapping,how,recurse)
local data = io.loaddata(filename) or ""
if mapping and next(mapping) then
return replace(data,mapping,how,recurse)
else
return data
end
end
function templates.resolve(t,mapping,how,recurse)
if not mapping then
mapping = t
end
for k, v in next, t do
t[k] = replace(v,mapping,how,recurse)
end
return t
end
-- inspect(utilities.templates.replace("test %one% test", { one = "%two%", two = "two" }))
-- inspect(utilities.templates.resolve({ one = "%two%", two = "two", three = "%three%" }))
-- inspect(utilities.templates.replace("test %one% test", { one = "%two%", two = "two" },false,true))
-- inspect(utilities.templates.replace("test %one% test", { one = "%two%", two = "two" },false))