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-rw-r--r--macros/luatex/generic/penlight/pl/MultiMap.lua54
1 files changed, 54 insertions, 0 deletions
diff --git a/macros/luatex/generic/penlight/pl/MultiMap.lua b/macros/luatex/generic/penlight/pl/MultiMap.lua
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+++ b/macros/luatex/generic/penlight/pl/MultiMap.lua
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+--- MultiMap, a Map which has multiple values per key.
+--
+-- Dependencies: `pl.utils`, `pl.class`, `pl.List`, `pl.Map`
+-- @classmod pl.MultiMap
+
+local utils = require 'pl.utils'
+local class = require 'pl.class'
+local List = require 'pl.List'
+local Map = require 'pl.Map'
+
+-- MultiMap is a standard MT
+local MultiMap = utils.stdmt.MultiMap
+
+class(Map,nil,MultiMap)
+MultiMap._name = 'MultiMap'
+
+function MultiMap:_init (t)
+ if not t then return end
+ self:update(t)
+end
+
+--- update a MultiMap using a table.
+-- @param t either a Multimap or a map-like table.
+-- @return the map
+function MultiMap:update (t)
+ utils.assert_arg(1,t,'table')
+ if Map:class_of(t) then
+ for k,v in pairs(t) do
+ self[k] = List()
+ self[k]:append(v)
+ end
+ else
+ for k,v in pairs(t) do
+ self[k] = List(v)
+ end
+ end
+end
+
+--- add a new value to a key. Setting a nil value removes the key.
+-- @param key the key
+-- @param val the value
+-- @return the map
+function MultiMap:set (key,val)
+ if val == nil then
+ self[key] = nil
+ else
+ if not self[key] then
+ self[key] = List()
+ end
+ self[key]:append(val)
+ end
+end
+
+return MultiMap