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diff --git a/Master/texmf-dist/tex/context/base/mkxl/attr-alt.lmt b/Master/texmf-dist/tex/context/base/mkxl/attr-alt.lmt
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+if not modules then modules = { } end modules ['attr-eff'] = {
+ version = 1.001,
+ comment = "companion to attr-eff.mkiv",
+ author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+ copyright = "PRAGMA ADE / ConTeXt Development Team",
+ license = "see context related readme files"
+}
+
+local attributes, nodes, backends, utilities = attributes, nodes, backends, utilities
+local tex = tex
+
+local states = attributes.states
+local enableaction = nodes.tasks.enableaction
+local nodeinjections = backends.nodeinjections
+local texsetattribute = tex.setattribute
+local allocate = utilities.storage.allocate
+local setmetatableindex = table.setmetatableindex
+
+local interfaces = interfaces
+local implement = interfaces.implement
+
+attributes.alternates = attributes.alternates or { }
+local alternates = attributes.alternates
+
+local a_alternate = attributes.private('alternate')
+
+alternates.data = allocate()
+alternates.values = alternates.values or { }
+alternates.registered = alternates.registered or { }
+alternates.attribute = a_alternate
+
+local data = alternates.data
+local registered = alternates.registered
+local values = alternates.values
+
+storage.register("attributes/alternates/registered", registered, "attributes.alternates.registered")
+storage.register("attributes/alternates/values", values, "attributes.alternates.values")
+
+local function extender(alternates,key)
+ if key == "none" then
+ local d = nodeinjections.stopalternate()
+ alternates.none = d
+ return d
+ end
+end
+
+local function reviver(data,n)
+ local d = values[n] and nodeinjections.startalternate(values[n]) or nodeinjections.stopalternate()
+ data[n] = d
+ return d
+end
+
+setmetatableindex(alternates, extender)
+setmetatableindex(alternates.data, reviver)
+
+alternates.handler = nodes.installattributehandler {
+ name = "alternate",
+ namespace = alternates,
+ initializer = states.initialize,
+ finalizer = states.finalize,
+ processor = states.simple,
+}
+
+local function register(specification)
+ local text = specification.text or "unknown"
+ local n = registered[text]
+ if not n then
+ n = #values + 1
+ values[n] = text
+ registered[text] = n
+ end
+ return n
+end
+
+local enabled = false
+
+local function enable()
+ if not enabled then
+ enableaction("shipouts","attributes.alternates.handler")
+ enabled = true
+ end
+end
+
+alternates.register = register
+alternates.enable = enable
+
+-- interface
+
+implement {
+ name = "setalternate",
+ actions = function(specification)
+ if not enabled then
+ enable()
+ end
+ texsetattribute(a_alternate,register(specification))
+ end,
+ arguments = {
+ {
+ { "text", "string" },
+ }
+ }
+}
+
+implement {
+ name = "resetalternate",
+ actions = function()
+ if enabled then
+ texsetattribute(a_alternate)
+ end
+ end
+}