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diff --git a/indra/newview/scripts/lua/require/util.lua b/indra/newview/scripts/lua/require/util.lua
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+++ b/indra/newview/scripts/lua/require/util.lua
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+-- utility functions, in alpha order
+
+local util = {}
+
+-- Allow MyClass(ctor args...) equivalent to MyClass:new(ctor args...)
+-- Usage:
+-- local MyClass = {}
+-- function MyClass:new(...)
+--     ...
+-- end
+-- ...
+-- util.classctor(MyClass)
+-- or if your constructor is named something other than MyClass:new(), e.g.
+-- MyClass:construct():
+-- util.classctor(MyClass, MyClass.construct)
+-- return MyClass
+function util.classctor(class, ctor)
+    -- set class's __call metamethod to the specified constructor function
+    -- (class.new if not specified)
+    util.setmetamethods{class, __call=(ctor or class.new)}
+end
+
+-- check if array-like table contains certain value
+function util.contains(t, v)
+    return table.find(t, v) ~= nil
+end
+
+-- reliable count of the number of entries in table t
+-- (since #t is unreliable)
+function util.count(t)
+    local count = 0
+    for _ in pairs(t) do
+        count += 1
+    end
+    return count
+end
+
+-- cheap test whether table t is empty
+function util.empty(t)
+    return not next(t)
+end
+
+-- recursive table equality
+function util.equal(t1, t2)
+    if not (type(t1) == 'table' and type(t2) == 'table') then
+        return t1 == t2
+    end
+    -- both t1 and t2 are tables: get modifiable copy of t2
+    local temp = table.clone(t2)
+    for k, v in pairs(t1) do
+        -- if any key in t1 doesn't have same value in t2, not equal
+        if not util.equal(v, temp[k]) then
+            return false
+        end
+        -- temp[k] == t1[k], delete temp[k]
+        temp[k] = nil
+    end
+    -- All keys in t1 have equal values in t2; t2 == t1 if there are no extra keys in t2
+    return util.empty(temp)
+end
+
+-- Find or create the metatable for a specified table (a new empty table if
+-- omitted), and to that metatable assign the specified keys.
+-- Setting multiple keys at once is more efficient than a function to set only
+-- one at a time, e.g. setametamethod().
+-- t = util.setmetamethods{__index=readfunc, __len=lenfunc}
+-- returns a new table with specified metamethods __index, __len
+-- util.setmetamethods{t, __call=action}
+-- finds or creates the metatable for existing table t and sets __call
+-- util.setmetamethods{table=t, __call=action}
+-- same as util.setmetamethods{t, __call=action}
+function util.setmetamethods(specs)
+    -- first determine the target table
+    assert(not (specs.table and specs[1]),
+           "Pass setmetamethods table either as positional or table=, not both")
+    local t = specs.table or specs[1] or {}
+    -- remove both ways of specifying table, leaving only the metamethods
+    specs.table = nil
+    specs[1] = nil
+    local mt = getmetatable(t)
+    if not mt then
+        -- t doesn't already have a metatable: just set specs
+        setmetatable(t, specs)
+    else
+        -- t already has a metatable: copy specs into it
+        local key, value
+        for key, value in pairs(specs) do
+            mt[key] = value
+        end
+    end
+    -- having set or enriched t's metatable, return t
+    return t
+end
+
+-- On the passed module (i.e. table), set an __index metamethod such that
+-- referencing module.submodule lazily requires(path/submodule).
+-- The loaded submodule is cached in the module table so it need not be passed
+-- to require() again.
+-- 'path', like any require() string, can be relative to LuaRequirePath.
+-- Returns the enriched module, permitting e.g.
+-- mymod = util.submoduledir({}, 'mymod')
+function util.submoduledir(module, path)
+    return util.setmetamethods{
+        module,
+        __index=function(t, key)
+            local mod = require(`{path}/{key}`)
+            -- cache the submodule
+            t[key] = mod
+            return mod
+        end
+    }
+end
+
+return util