diff options
Diffstat (limited to 'tex/context/base/l-table.lua')
| -rw-r--r-- | tex/context/base/l-table.lua | 50 |
1 files changed, 48 insertions, 2 deletions
diff --git a/tex/context/base/l-table.lua b/tex/context/base/l-table.lua index ea675b081..ca067fb1e 100644 --- a/tex/context/base/l-table.lua +++ b/tex/context/base/l-table.lua @@ -164,14 +164,14 @@ local function sortedhash(t,cmp) end local n = 0 local m = #s - local function kv(s) + local function kv() -- (s) if n < m then n = n + 1 local k = s[n] return k, t[k] end end - return kv, s + return kv -- , s else return nothing end @@ -1114,3 +1114,49 @@ function table.values(t,s) -- optional sort flag return { } end end + +-- maybe this will move to util-tab.lua + +-- for k, v in table.filtered(t,pattern) do ... end +-- for k, v in table.filtered(t,pattern,true) do ... end +-- for k, v in table.filtered(t,pattern,true,cmp) do ... end + +function table.filtered(t,pattern,sort,cmp) + if t and type(pattern) == "string" then + if sort then + local s + if cmp then + -- it would be nice if the sort function would accept a third argument (or nicer, an optional first) + s = sortedhashkeys(t,function(a,b) return cmp(t,a,b) end) + else + s = sortedkeys(t) -- the robust one + end + local n = 0 + local m = #s + local function kv(s) + while n < m do + n = n + 1 + local k = s[n] + if find(k,pattern) then + return k, t[k] + end + end + end + return kv, s + else + local n = next(t) + local function iterator() + while n do + local k = n + n = next(t,k) + if find(k,pattern) then + return k, t[k] + end + end + end + return iterator, t + end + else + return nothing + end +end |