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authorKhaled Hosny <khaledhosny@eglug.org>2010-01-11 15:15:52 +0200
committerKhaled Hosny <khaledhosny@eglug.org>2010-01-11 16:03:13 +0200
commitf1c3cb9dc199c28cdd2c813eb1ea5c21345125d0 (patch)
tree808986ca292251a39a2fc9fa3a7e01b9e761577e /luaextra-table.lua
parente5ad063f805ecbf5fd093712bc60ef5aec25a6fd (diff)
downloadlualibs-f1c3cb9dc199c28cdd2c813eb1ea5c21345125d0.tar.gz
Import ConTeX's lua libraries
Replace most of luaextra.lua with a bunch of require() calls and add renamed (but unmodified) ConTeX lua libraries to the repository. ConTeXt's l-xml.lua module has been excluded because it depends on a bunch of other ConTeXt specific modules. Also l-pdfview.lua has been dropped, I don't know what to use it for.
Diffstat (limited to 'luaextra-table.lua')
-rw-r--r--luaextra-table.lua858
1 files changed, 858 insertions, 0 deletions
diff --git a/luaextra-table.lua b/luaextra-table.lua
new file mode 100644
index 0000000..70a901e
--- /dev/null
+++ b/luaextra-table.lua
@@ -0,0 +1,858 @@
+if not modules then modules = { } end modules ['l-table'] = {
+ 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"
+}
+
+table.join = table.concat
+
+local concat, sort, insert, remove = table.concat, table.sort, table.insert, table.remove
+local format, find, gsub, lower, dump, match = string.format, string.find, string.gsub, string.lower, string.dump, string.match
+local getmetatable, setmetatable = getmetatable, setmetatable
+local type, next, tostring, tonumber, ipairs, pairs = type, next, tostring, tonumber, ipairs, pairs
+
+function table.strip(tab)
+ local lst = { }
+ for i=1,#tab do
+ local s = gsub(tab[i],"^%s*(.-)%s*$","%1")
+ if s == "" then
+ -- skip this one
+ else
+ lst[#lst+1] = s
+ end
+ end
+ return lst
+end
+
+function table.keys(t)
+ local k = { }
+ for key,_ in next, t do
+ k[#k+1] = key
+ end
+ return k
+end
+
+local function compare(a,b)
+ return (tostring(a) < tostring(b))
+end
+
+local function sortedkeys(tab)
+ local srt, kind = { }, 0 -- 0=unknown 1=string, 2=number 3=mixed
+ for key,_ in next, tab do
+ srt[#srt+1] = key
+ if kind == 3 then
+ -- no further check
+ else
+ local tkey = type(key)
+ if tkey == "string" then
+ -- if kind == 2 then kind = 3 else kind = 1 end
+ kind = (kind == 2 and 3) or 1
+ elseif tkey == "number" then
+ -- if kind == 1 then kind = 3 else kind = 2 end
+ kind = (kind == 1 and 3) or 2
+ else
+ kind = 3
+ end
+ end
+ end
+ if kind == 0 or kind == 3 then
+ sort(srt,compare)
+ else
+ sort(srt)
+ end
+ return srt
+end
+
+local function sortedhashkeys(tab) -- fast one
+ local srt = { }
+ for key,_ in next, tab do
+ srt[#srt+1] = key
+ end
+ sort(srt)
+ return srt
+end
+
+table.sortedkeys = sortedkeys
+table.sortedhashkeys = sortedhashkeys
+
+function table.sortedpairs(t)
+ local s = sortedhashkeys(t) -- maybe just sortedkeys
+ local n = 0
+ local function kv(s)
+ n = n + 1
+ local k = s[n]
+ return k, t[k]
+ end
+ return kv, s
+end
+
+function table.append(t, list)
+ for _,v in next, list do
+ insert(t,v)
+ end
+end
+
+function table.prepend(t, list)
+ for k,v in next, list do
+ insert(t,k,v)
+ end
+end
+
+function table.merge(t, ...) -- first one is target
+ t = t or {}
+ local lst = {...}
+ for i=1,#lst do
+ for k, v in next, lst[i] do
+ t[k] = v
+ end
+ end
+ return t
+end
+
+function table.merged(...)
+ local tmp, lst = { }, {...}
+ for i=1,#lst do
+ for k, v in next, lst[i] do
+ tmp[k] = v
+ end
+ end
+ return tmp
+end
+
+function table.imerge(t, ...)
+ local lst = {...}
+ for i=1,#lst do
+ local nst = lst[i]
+ for j=1,#nst do
+ t[#t+1] = nst[j]
+ end
+ end
+ return t
+end
+
+function table.imerged(...)
+ local tmp, lst = { }, {...}
+ for i=1,#lst do
+ local nst = lst[i]
+ for j=1,#nst do
+ tmp[#tmp+1] = nst[j]
+ end
+ end
+ return tmp
+end
+
+local function fastcopy(old) -- fast one
+ if old then
+ local new = { }
+ for k,v in next, old do
+ if type(v) == "table" then
+ new[k] = fastcopy(v) -- was just table.copy
+ else
+ new[k] = v
+ end
+ end
+ -- optional second arg
+ local mt = getmetatable(old)
+ if mt then
+ setmetatable(new,mt)
+ end
+ return new
+ else
+ return { }
+ end
+end
+
+local function copy(t, tables) -- taken from lua wiki, slightly adapted
+ tables = tables or { }
+ local tcopy = {}
+ if not tables[t] then
+ tables[t] = tcopy
+ end
+ for i,v in next, t do -- brrr, what happens with sparse indexed
+ if type(i) == "table" then
+ if tables[i] then
+ i = tables[i]
+ else
+ i = copy(i, tables)
+ end
+ end
+ if type(v) ~= "table" then
+ tcopy[i] = v
+ elseif tables[v] then
+ tcopy[i] = tables[v]
+ else
+ tcopy[i] = copy(v, tables)
+ end
+ end
+ local mt = getmetatable(t)
+ if mt then
+ setmetatable(tcopy,mt)
+ end
+ return tcopy
+end
+
+table.fastcopy = fastcopy
+table.copy = copy
+
+-- rougly: copy-loop : unpack : sub == 0.9 : 0.4 : 0.45 (so in critical apps, use unpack)
+
+function table.sub(t,i,j)
+ return { unpack(t,i,j) }
+end
+
+function table.replace(a,b)
+ for k,v in next, b do
+ a[k] = v
+ end
+end
+
+-- slower than #t on indexed tables (#t only returns the size of the numerically indexed slice)
+
+function table.is_empty(t)
+ return not t or not next(t)
+end
+
+function table.one_entry(t)
+ local n = next(t)
+ return n and not next(t,n)
+end
+
+function table.starts_at(t)
+ return ipairs(t,1)(t,0)
+end
+
+function table.tohash(t,value)
+ local h = { }
+ if t then
+ if value == nil then value = true end
+ for _, v in next, t do -- no ipairs here
+ h[v] = value
+ end
+ end
+ return h
+end
+
+function table.fromhash(t)
+ local h = { }
+ for k, v in next, t do -- no ipairs here
+ if v then h[#h+1] = k end
+ end
+ return h
+end
+
+--~ print(table.serialize(t), "\n")
+--~ print(table.serialize(t,"name"), "\n")
+--~ print(table.serialize(t,false), "\n")
+--~ print(table.serialize(t,true), "\n")
+--~ print(table.serialize(t,"name",true), "\n")
+--~ print(table.serialize(t,"name",true,true), "\n")
+
+table.serialize_functions = true
+table.serialize_compact = true
+table.serialize_inline = true
+
+local noquotes, hexify, handle, reduce, compact, inline, functions
+
+local reserved = table.tohash { -- intercept a language flaw, no reserved words as key
+ 'and', 'break', 'do', 'else', 'elseif', 'end', 'false', 'for', 'function', 'if',
+ 'in', 'local', 'nil', 'not', 'or', 'repeat', 'return', 'then', 'true', 'until', 'while',
+}
+
+local function simple_table(t)
+ if #t > 0 then
+ local n = 0
+ for _,v in next, t do
+ n = n + 1
+ end
+ if n == #t then
+ local tt = { }
+ for i=1,#t do
+ local v = t[i]
+ local tv = type(v)
+ if tv == "number" then
+ if hexify then
+ tt[#tt+1] = format("0x%04X",v)
+ else
+ tt[#tt+1] = tostring(v) -- tostring not needed
+ end
+ elseif tv == "boolean" then
+ tt[#tt+1] = tostring(v)
+ elseif tv == "string" then
+ tt[#tt+1] = format("%q",v)
+ else
+ tt = nil
+ break
+ end
+ end
+ return tt
+ end
+ end
+ return nil
+end
+
+-- Because this is a core function of mkiv I moved some function calls
+-- inline.
+--
+-- twice as fast in a test:
+--
+-- local propername = lpeg.P(lpeg.R("AZ","az","__") * lpeg.R("09","AZ","az", "__")^0 * lpeg.P(-1) )
+
+-- problem: there no good number_to_string converter with the best resolution
+
+local function do_serialize(root,name,depth,level,indexed)
+ if level > 0 then
+ depth = depth .. " "
+ if indexed then
+ handle(format("%s{",depth))
+ elseif name then
+ --~ handle(format("%s%s={",depth,key(name)))
+ if type(name) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s[0x%04X]={",depth,name))
+ else
+ handle(format("%s[%s]={",depth,name))
+ end
+ elseif noquotes and not reserved[name] and find(name,"^%a[%w%_]*$") then
+ handle(format("%s%s={",depth,name))
+ else
+ handle(format("%s[%q]={",depth,name))
+ end
+ else
+ handle(format("%s{",depth))
+ end
+ end
+ -- we could check for k (index) being number (cardinal)
+ if root and next(root) then
+ local first, last = nil, 0 -- #root cannot be trusted here
+ if compact then
+ -- NOT: for k=1,#root do (we need to quit at nil)
+ for k,v in ipairs(root) do -- can we use next?
+ if not first then first = k end
+ last = last + 1
+ end
+ end
+ local sk = sortedkeys(root)
+ for i=1,#sk do
+ local k = sk[i]
+ local v = root[k]
+ --~ if v == root then
+ -- circular
+ --~ else
+ local t = type(v)
+ if compact and first and type(k) == "number" and k >= first and k <= last then
+ if t == "number" then
+ if hexify then
+ handle(format("%s 0x%04X,",depth,v))
+ else
+ handle(format("%s %s,",depth,v)) -- %.99g
+ end
+ elseif t == "string" then
+ if reduce and tonumber(v) then
+ handle(format("%s %s,",depth,v))
+ else
+ handle(format("%s %q,",depth,v))
+ end
+ elseif t == "table" then
+ if not next(v) then
+ handle(format("%s {},",depth))
+ elseif inline then -- and #t > 0
+ local st = simple_table(v)
+ if st then
+ handle(format("%s { %s },",depth,concat(st,", ")))
+ else
+ do_serialize(v,k,depth,level+1,true)
+ end
+ else
+ do_serialize(v,k,depth,level+1,true)
+ end
+ elseif t == "boolean" then
+ handle(format("%s %s,",depth,tostring(v)))
+ elseif t == "function" then
+ if functions then
+ handle(format('%s loadstring(%q),',depth,dump(v)))
+ else
+ handle(format('%s "function",',depth))
+ end
+ else
+ handle(format("%s %q,",depth,tostring(v)))
+ end
+ elseif k == "__p__" then -- parent
+ if false then
+ handle(format("%s __p__=nil,",depth))
+ end
+ elseif t == "number" then
+ --~ if hexify then
+ --~ handle(format("%s %s=0x%04X,",depth,key(k),v))
+ --~ else
+ --~ handle(format("%s %s=%s,",depth,key(k),v)) -- %.99g
+ --~ end
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]=0x%04X,",depth,k,v))
+ else
+ handle(format("%s [%s]=%s,",depth,k,v)) -- %.99g
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ if hexify then
+ handle(format("%s %s=0x%04X,",depth,k,v))
+ else
+ handle(format("%s %s=%s,",depth,k,v)) -- %.99g
+ end
+ else
+ if hexify then
+ handle(format("%s [%q]=0x%04X,",depth,k,v))
+ else
+ handle(format("%s [%q]=%s,",depth,k,v)) -- %.99g
+ end
+ end
+ elseif t == "string" then
+ if reduce and tonumber(v) then
+ --~ handle(format("%s %s=%s,",depth,key(k),v))
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]=%s,",depth,k,v))
+ else
+ handle(format("%s [%s]=%s,",depth,k,v))
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ handle(format("%s %s=%s,",depth,k,v))
+ else
+ handle(format("%s [%q]=%s,",depth,k,v))
+ end
+ else
+ --~ handle(format("%s %s=%q,",depth,key(k),v))
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]=%q,",depth,k,v))
+ else
+ handle(format("%s [%s]=%q,",depth,k,v))
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ handle(format("%s %s=%q,",depth,k,v))
+ else
+ handle(format("%s [%q]=%q,",depth,k,v))
+ end
+ end
+ elseif t == "table" then
+ if not next(v) then
+ --~ handle(format("%s %s={},",depth,key(k)))
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]={},",depth,k))
+ else
+ handle(format("%s [%s]={},",depth,k))
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ handle(format("%s %s={},",depth,k))
+ else
+ handle(format("%s [%q]={},",depth,k))
+ end
+ elseif inline then
+ local st = simple_table(v)
+ if st then
+ --~ handle(format("%s %s={ %s },",depth,key(k),concat(st,", ")))
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]={ %s },",depth,k,concat(st,", ")))
+ else
+ handle(format("%s [%s]={ %s },",depth,k,concat(st,", ")))
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ handle(format("%s %s={ %s },",depth,k,concat(st,", ")))
+ else
+ handle(format("%s [%q]={ %s },",depth,k,concat(st,", ")))
+ end
+ else
+ do_serialize(v,k,depth,level+1)
+ end
+ else
+ do_serialize(v,k,depth,level+1)
+ end
+ elseif t == "boolean" then
+ --~ handle(format("%s %s=%s,",depth,key(k),tostring(v)))
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]=%s,",depth,k,tostring(v)))
+ else
+ handle(format("%s [%s]=%s,",depth,k,tostring(v)))
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ handle(format("%s %s=%s,",depth,k,tostring(v)))
+ else
+ handle(format("%s [%q]=%s,",depth,k,tostring(v)))
+ end
+ elseif t == "function" then
+ if functions then
+ --~ handle(format('%s %s=loadstring(%q),',depth,key(k),dump(v)))
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]=loadstring(%q),",depth,k,dump(v)))
+ else
+ handle(format("%s [%s]=loadstring(%q),",depth,k,dump(v)))
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ handle(format("%s %s=loadstring(%q),",depth,k,dump(v)))
+ else
+ handle(format("%s [%q]=loadstring(%q),",depth,k,dump(v)))
+ end
+ end
+ else
+ --~ handle(format("%s %s=%q,",depth,key(k),tostring(v)))
+ if type(k) == "number" then -- or find(k,"^%d+$") then
+ if hexify then
+ handle(format("%s [0x%04X]=%q,",depth,k,tostring(v)))
+ else
+ handle(format("%s [%s]=%q,",depth,k,tostring(v)))
+ end
+ elseif noquotes and not reserved[k] and find(k,"^%a[%w%_]*$") then
+ handle(format("%s %s=%q,",depth,k,tostring(v)))
+ else
+ handle(format("%s [%q]=%q,",depth,k,tostring(v)))
+ end
+ end
+ --~ end
+ end
+ end
+ if level > 0 then
+ handle(format("%s},",depth))
+ end
+end
+
+-- replacing handle by a direct t[#t+1] = ... (plus test) is not much
+-- faster (0.03 on 1.00 for zapfino.tma)
+
+local function serialize(root,name,_handle,_reduce,_noquotes,_hexify)
+ noquotes = _noquotes
+ hexify = _hexify
+ handle = _handle or print
+ reduce = _reduce or false
+ compact = table.serialize_compact
+ inline = compact and table.serialize_inline
+ functions = table.serialize_functions
+ local tname = type(name)
+ if tname == "string" then
+ if name == "return" then
+ handle("return {")
+ else
+ handle(name .. "={")
+ end
+ elseif tname == "number" then
+ if hexify then
+ handle(format("[0x%04X]={",name))
+ else
+ handle("[" .. name .. "]={")
+ end
+ elseif tname == "boolean" then
+ if name then
+ handle("return {")
+ else
+ handle("{")
+ end
+ else
+ handle("t={")
+ end
+ if root and next(root) then
+ do_serialize(root,name,"",0,indexed)
+ end
+ handle("}")
+end
+
+--~ name:
+--~
+--~ true : return { }
+--~ false : { }
+--~ nil : t = { }
+--~ string : string = { }
+--~ 'return' : return { }
+--~ number : [number] = { }
+
+function table.serialize(root,name,reduce,noquotes,hexify)
+ local t = { }
+ local function flush(s)
+ t[#t+1] = s
+ end
+ serialize(root,name,flush,reduce,noquotes,hexify)
+ return concat(t,"\n")
+end
+
+function table.tohandle(handle,root,name,reduce,noquotes,hexify)
+ serialize(root,name,handle,reduce,noquotes,hexify)
+end
+
+-- sometimes tables are real use (zapfino extra pro is some 85M) in which
+-- case a stepwise serialization is nice; actually, we could consider:
+--
+-- for line in table.serializer(root,name,reduce,noquotes) do
+-- ...(line)
+-- end
+--
+-- so this is on the todo list
+
+table.tofile_maxtab = 2*1024
+
+function table.tofile(filename,root,name,reduce,noquotes,hexify)
+ local f = io.open(filename,'w')
+ if f then
+ local maxtab = table.tofile_maxtab
+ if maxtab > 1 then
+ local t = { }
+ local function flush(s)
+ t[#t+1] = s
+ if #t > maxtab then
+ f:write(concat(t,"\n"),"\n") -- hm, write(sometable) should be nice
+ t = { }
+ end
+ end
+ serialize(root,name,flush,reduce,noquotes,hexify)
+ f:write(concat(t,"\n"),"\n")
+ else
+ local function flush(s)
+ f:write(s,"\n")
+ end
+ serialize(root,name,flush,reduce,noquotes,hexify)
+ end
+ f:close()
+ end
+end
+
+local function flatten(t,f,complete) -- is this used? meybe a variant with next, ...
+ for i=1,#t do
+ local v = t[i]
+ if type(v) == "table" then
+ if complete or type(v[1]) == "table" then
+ flatten(v,f,complete)
+ else
+ f[#f+1] = v
+ end
+ else
+ f[#f+1] = v
+ end
+ end
+end
+
+function table.flatten(t)
+ local f = { }
+ flatten(t,f,true)
+ return f
+end
+
+function table.unnest(t) -- bad name
+ local f = { }
+ flatten(t,f,false)
+ return f
+end
+
+table.flatten_one_level = table.unnest
+
+-- a better one:
+
+local function flattened(t,f)
+ if not f then
+ f = { }
+ end
+ for k, v in next, t do
+ if type(v) == "table" then
+ flattened(v,f)
+ else
+ f[k] = v
+ end
+ end
+ return f
+end
+
+table.flattened = flattened
+
+-- the next three may disappear
+
+function table.remove_value(t,value) -- todo: n
+ if value then
+ for i=1,#t do
+ if t[i] == value then
+ remove(t,i)
+ -- remove all, so no: return
+ end
+ end
+ end
+end
+
+function table.insert_before_value(t,value,str)
+ if str then
+ if value then
+ for i=1,#t do
+ if t[i] == value then
+ insert(t,i,str)
+ return
+ end
+ end
+ end
+ insert(t,1,str)
+ elseif value then
+ insert(t,1,value)
+ end
+end
+
+function table.insert_after_value(t,value,str)
+ if str then
+ if value then
+ for i=1,#t do
+ if t[i] == value then
+ insert(t,i+1,str)
+ return
+ end
+ end
+ end
+ t[#t+1] = str
+ elseif value then
+ t[#t+1] = value
+ end
+end
+
+local function are_equal(a,b,n,m) -- indexed
+ if a and b and #a == #b then
+ n = n or 1
+ m = m or #a
+ for i=n,m do
+ local ai, bi = a[i], b[i]
+ if ai==bi then
+ -- same
+ elseif type(ai)=="table" and type(bi)=="table" then
+ if not are_equal(ai,bi) then
+ return false
+ end
+ else
+ return false
+ end
+ end
+ return true
+ else
+ return false
+ end
+end
+
+local function identical(a,b) -- assumes same structure
+ for ka, va in next, a do
+ local vb = b[k]
+ if va == vb then
+ -- same
+ elseif type(va) == "table" and type(vb) == "table" then
+ if not identical(va,vb) then
+ return false
+ end
+ else
+ return false
+ end
+ end
+ return true
+end
+
+table.are_equal = are_equal
+table.identical = identical
+
+-- maybe also make a combined one
+
+function table.compact(t)
+ if t then
+ for k,v in next, t do
+ if not next(v) then
+ t[k] = nil
+ end
+ end
+ end
+end
+
+function table.contains(t, v)
+ if t then
+ for i=1, #t do
+ if t[i] == v then
+ return i
+ end
+ end
+ end
+ return false
+end
+
+function table.count(t)
+ local n, e = 0, next(t)
+ while e do
+ n, e = n + 1, next(t,e)
+ end
+ return n
+end
+
+function table.swapped(t)
+ local s = { }
+ for k, v in next, t do
+ s[v] = k
+ end
+ return s
+end
+
+--~ function table.are_equal(a,b)
+--~ return table.serialize(a) == table.serialize(b)
+--~ end
+
+function table.clone(t,p) -- t is optional or nil or table
+ if not p then
+ t, p = { }, t or { }
+ elseif not t then
+ t = { }
+ end
+ setmetatable(t, { __index = function(_,key) return p[key] end }) -- why not __index = p ?
+ return t
+end
+
+function table.hexed(t,seperator)
+ local tt = { }
+ for i=1,#t do tt[i] = format("0x%04X",t[i]) end
+ return concat(tt,seperator or " ")
+end
+
+function table.reverse_hash(h)
+ local r = { }
+ for k,v in next, h do
+ r[v] = lower(gsub(k," ",""))
+ end
+ return r
+end
+
+function table.reverse(t)
+ local tt = { }
+ if #t > 0 then
+ for i=#t,1,-1 do
+ tt[#tt+1] = t[i]
+ end
+ end
+ return tt
+end
+
+function table.insert_before_value(t,value,extra)
+ for i=1,#t do
+ if t[i] == extra then
+ remove(t,i)
+ end
+ end
+ for i=1,#t do
+ if t[i] == value then
+ insert(t,i,extra)
+ return
+ end
+ end
+ insert(t,1,extra)
+end
+
+function table.insert_after_value(t,value,extra)
+ for i=1,#t do
+ if t[i] == extra then
+ remove(t,i)
+ end
+ end
+ for i=1,#t do
+ if t[i] == value then
+ insert(t,i+1,extra)
+ return
+ end
+ end
+ insert(t,#t+1,extra)
+end