From e4fe19362f79e40fbfd2b436e3e0851c6b13a991 Mon Sep 17 00:00:00 2001 From: Matthew Wild Date: Sat, 19 May 2012 04:12:41 +0100 Subject: util.multitable: Add :iter() method to iterate over results at a fixed depth (parameters are equivalent to :search()) --- util/multitable.lua | 43 ++++++++++++++++++++++++++++++++++++++----- 1 file changed, 38 insertions(+), 5 deletions(-) (limited to 'util/multitable.lua') diff --git a/util/multitable.lua b/util/multitable.lua index 66b9bd8a..388f60f3 100644 --- a/util/multitable.lua +++ b/util/multitable.lua @@ -6,12 +6,9 @@ -- COPYING file in the source package for more information. -- - - local select = select; -local t_insert = table.insert; -local pairs = pairs; -local next = next; +local t_insert, t_remove = table.insert, table.remove; +local unpack, pairs, next, type = unpack, pairs, next, type; module "multitable" @@ -129,6 +126,41 @@ local function search_add(self, results, ...) return results; end +function iter(self, ...) + local query = { ... }; + local maxdepth = select("#", ...); + local stack = { self.data }; + local keys = { }; + local function it(self) + local depth = #stack; + local key = next(stack[depth], keys[depth]); + if key == nil then -- Go up the stack + t_remove(stack); + t_remove(keys); + if depth > 1 then + return it(self); + end + return; -- The end + else + keys[depth] = key; + end + local value = stack[depth][key]; + if depth == maxdepth then -- Result + local result = {}; -- Collect keys forming path to result + for i = 1, depth do + result[i] = keys[i]; + end + return unpack(result, 1, depth); + else + if (query[depth] == nil or key == query[depth]) and type(value) == "table" then -- Descend + t_insert(stack, value); + end + return it(self); + end + end; + return it, self; +end + function new() return { data = {}; @@ -138,6 +170,7 @@ function new() remove = remove; search = search; search_add = search_add; + iter = iter; }; end -- cgit v1.2.3