1 files changed, 105 insertions, 0 deletions
diff --git a/tex/context/base/font-aux.lua b/tex/context/base/font-aux.lua
new file mode 100644
index 000000000..a3e717b44
--- /dev/null
+++ b/tex/context/base/font-aux.lua
@@ -0,0 +1,105 @@
+if not modules then modules = { } end modules ['font-aux'] = {
+    version   = 1.001,
+    comment   = "companion to font-ini.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+local number = tonumber
+local wrap, yield = coroutine.wrap, coroutine.yield
+
+local fonts, font = fonts, font
+
+local iterators   = { }
+fonts.interators  = iterators
+
+local currentfont = font.current
+local identifiers = fonts.hashes.identifiers
+local sortedkeys  = table.sortedkeys
+
+-- for unicode, character   in fonts.iterators.characters  () do print(k,v) end
+-- for unicode, description in fonts.iterators.descriptions() do print(k,v) end
+-- for index,   glyph       in fonts.iterators.glyphs      () do print(k,v) end
+
+
+local function checkeddata(data) -- beware, nullfont is the fallback in identifiers
+    local t = type(data)
+    if t == "table" then
+        return data
+    elseif t ~= "number" then
+        data = currentfont()
+    end
+    return identifiers[data] -- has nullfont as fallback
+end
+
+function iterators.characters(data)
+    data = checkeddata(data)
+    local characters = data.characters
+    if characters then
+        local collected  = sortedkeys(characters)
+        return wrap(function()
+            for c=1,#collected do
+                local cc = collected[c]
+                local dc = characters[cc]
+                if dc then
+                    yield(cc,dc)
+                end
+            end
+        end)
+    else
+        return wrap(function() end)
+    end
+end
+
+function iterators.descriptions(data)
+    data = checkeddata(data)
+    local characters = data.characters
+    local descriptions = data.descriptions
+    if characters and descriptions then
+        local collected = sortedkeys(characters)
+        return wrap(function()
+            for c=1,#collected do
+                local cc = collected[c]
+                local dc = descriptions[cc]
+                if dc then
+                    yield(cc,dc)
+                end
+            end
+        end)
+    else
+        return wrap(function() end)
+    end
+end
+
+local function getindices(data)
+    data = checkeddata(data)
+    local indices = { }
+    local characters = data.characters
+    if characters then
+        for unicode, character in next, characters do
+            indices[character.index or unicode] = unicode
+        end
+    end
+    return indices
+end
+
+function iterators.glyphs(data)
+    data = checkeddata(data)
+    local descriptions = data.descriptions
+    if descriptions then
+        local indices = getindices(data)
+        local collected = sortedkeys(indices)
+        return wrap(function()
+            for c=1,#collected do
+                local cc = collected[c]
+                local dc = descriptions[indices[cc]]
+                if dc then
+                    yield(cc,dc)
+                end
+            end
+        end)
+    else
+        return wrap(function() end)
+    end
+end