beta 2011.03.25 18:03

1 files changed, 120 insertions, 0 deletions

diff --git a/tex/context/base/scrn-hlp.lua b/tex/context/base/scrn-hlp.lua
new file mode 100644
index 000000000..81d68840b
--- /dev/null
+++ b/tex/context/base/scrn-hlp.lua
@@ -0,0 +1,120 @@
+if not modules then modules = { } end modules ['scrn-hlp'] = {
+    version   = 1.001,
+    comment   = "companion to scrn-hlp.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+local format = string.format
+
+local help           = { }
+interactions.help    = help
+
+local a_help         = attributes.private("help")
+
+local has_attribute  = node.has_attribute
+local copy_nodelist  = node.copy_list
+local hpack_nodelist = node.hpack
+
+local register_list  = nodes.pool.register
+
+local nodecodes      = nodes.nodecodes
+
+local hlist_code     = nodecodes.hlist
+local vlist_code     = nodecodes.vlist
+
+local data, references = { }, { }
+
+local helpscript = [[
+    function Hide_All_Help(prefix) {
+        var n = 0
+        while (true) {
+            n += 1 ;
+            v = this.getField(prefix + n) ;
+            if (v) {
+                v.hidden = true ;
+                this.dirty = false ;
+            } else {
+                return ;
+            }
+        }
+    }
+]]
+
+local template = "javascript(Hide_All_Help{help:}),action(show{help:%s})"
+
+function help.register(number,name,box)
+    if helpscript then
+        interactions.javascripts.setpreamble("HelpTexts",helpscript)
+        helpscript = false
+    end
+    local b = copy_nodelist(tex.box[box])
+    register_list(b)
+    data[number] = b
+    if name and name ~= "" then
+        references[name] = number
+        structures.references.define("",name,format(template,number))
+    end
+end
+
+local function collect(head,used)
+    while head do
+        local id = head.id
+        if id == hlist_code then
+            local a = has_attribute(head,a_help)
+            if a then
+                if not used then
+                    used = { a }
+                else
+                    used[#used+1] = a
+                end
+            else
+                used = collect(head.list,used)
+            end
+        elseif id == vlist_code then
+            used = collect(head.list,used)
+        end
+        head = head.next
+    end
+    return used
+end
+
+function help.collect(box)
+    if next(data) then
+        return collect(tex.box[box].list)
+    end
+end
+
+commands.registerhelp = help.register
+
+function commands.collecthelp(box)
+    local used = help.collect(box)
+    if used then
+        local done = { }
+        context.startoverlay()
+        for i=1,#used do
+            local d = data[used[i]]
+            if d and not done[d] then
+                local box = hpack_nodelist(copy_nodelist(d))
+                context(false,box)
+                done[d] = true
+            else
+                -- error
+            end
+        end
+        context.stopoverlay()
+    end
+end
+
+function help.reference(name)
+    return references[name] or tonumber(name) or 0
+end
+
+function commands.helpreference(name)
+    context(references[name] or tonumber(name) or 0)
+end
+
+function commands.helpaction(name)
+    context(template,references[name] or tonumber(name) or 0)
+end