stable 2012.05.30 11:26

1 files changed, 118 insertions, 0 deletions

diff --git a/tex/context/base/node-par.lua b/tex/context/base/node-par.lua
new file mode 100644
index 000000000..8eafd1f6e
--- /dev/null
+++ b/tex/context/base/node-par.lua
@@ -0,0 +1,118 @@
+if not modules then modules = { } end modules ['node-par'] = {
+    version   = 1.001,
+    comment   = "companion to node-par.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+local builders, nodes, node = builders, nodes, node
+
+builders.paragraphs      = builders.paragraphs or { }
+local parbuilders        = builders.paragraphs
+
+parbuilders.constructors = parbuilders.constructors or { }
+local       constructors = parbuilders.constructors
+
+constructors.names       = constructors.names or { }
+local names              = constructors.names
+
+constructors.numbers     = constructors.numbers or { }
+local numbers            = constructors.numbers
+
+constructors.methods     = constructors.methods or { }
+local methods            = constructors.methods
+
+local p_attribute        = attributes.numbers['parbuilder'] or 999
+constructors.attribute   = p_attribute
+
+local has_attribute      = node.has_attribute
+local starttiming        = statistics.starttiming
+local stoptiming         = statistics.stoptiming
+
+storage.register("builders/paragraphs/constructors/names",   names,   "builders.paragraphs.constructors.names")
+storage.register("builders/paragraphs/constructors/numbers", numbers, "builders.paragraphs.constructors.numbers")
+
+local report_parbuilders = logs.reporter("parbuilders")
+
+local mainconstructor = nil -- not stored in format
+
+function constructors.register(name,number)
+    names[number] = name
+    numbers[name] = number
+end
+
+function constructors.set(name)
+    mainconstructor = numbers[name]
+end
+
+-- return values:
+--
+-- true  : tex will break itself
+-- false : idem but dangerous
+-- head  : list of valid vmode nodes with last being hlist
+
+function constructors.handler(head,followed_by_display)
+    if type(head) == "boolean" then
+        return head
+    else
+        local attribute = has_attribute(head,p_attribute) or mainconstructor
+        if attribute then
+            local method = names[attribute]
+            if method then
+                local handler = methods[method]
+                if handler then
+                    return handler(head,followed_by_display)
+                else
+                    report_parbuilders("contructor method '%s' is not defined",tostring(method))
+                    return true -- let tex break
+                end
+            end
+        end
+        return true -- let tex break
+    end
+end
+
+-- just for testing
+
+function constructors.methods.default(head,followed_by_display)
+    return true -- let tex break
+end
+
+-- also for testing (no surrounding spacing done)
+
+function constructors.methods.oneline(head,followed_by_display)
+    return node.hpack(head)
+end
+
+-- It makes no sense to have a sequence here as we already have
+-- pre and post hooks and only one parbuilder makes sense, so no:
+--
+-- local actions = nodes.tasks.actions("parbuilders")
+--
+-- yet (maybe some day).
+--
+-- todo: enable one as main
+
+local actions = constructors.handler
+local enabled = false
+
+function constructors.enable () enabled = true  end
+function constructors.disable() enabled = false end
+
+local function processor(head,followed_by_display)
+    if enabled then
+        starttiming(parbuilders)
+        local head = actions(head,followed_by_display)
+        stoptiming(parbuilders)
+        return head
+    else
+        return true -- let tex do the work
+    end
+end
+
+callbacks.register('linebreak_filter', processor, "breaking paragraps into lines")
+
+statistics.register("linebreak processing time", function()
+    return statistics.elapsedseconds(parbuilders)
+end)