1 files changed, 33 insertions, 6 deletions
diff --git a/tex/context/base/mkiv/l-string.lua b/tex/context/base/mkiv/l-string.lua
index e9dc2bbbc..e0fb28445 100644
--- a/tex/context/base/mkiv/l-string.lua
+++ b/tex/context/base/mkiv/l-string.lua
@@ -72,22 +72,27 @@ end
 local stripper     = patterns.stripper
 local fullstripper = patterns.fullstripper
 local collapser    = patterns.collapser
+local nospacer     = patterns.nospacer
 local longtostring = patterns.longtostring
 
 function string.strip(str)
-    return lpegmatch(stripper,str) or ""
+    return str and lpegmatch(stripper,str) or ""
 end
 
 function string.fullstrip(str)
-    return lpegmatch(fullstripper,str) or ""
+    return str and lpegmatch(fullstripper,str) or ""
 end
 
 function string.collapsespaces(str)
-    return lpegmatch(collapser,str) or ""
+    return str and lpegmatch(collapser,str) or ""
+end
+
+function string.nospaces(str)
+    return str and lpegmatch(nospacer,str) or ""
 end
 
 function string.longtostring(str)
-    return lpegmatch(longtostring,str) or ""
+    return str and lpegmatch(longtostring,str) or ""
 end
 
 -- function string.is_empty(str)
@@ -99,7 +104,7 @@ local pattern = P(" ")^0 * P(-1) -- maybe also newlines
 -- patterns.onlyspaces = pattern
 
 function string.is_empty(str)
-    if str == "" then
+    if not str or str == "" then
         return true
     else
         return lpegmatch(pattern,str) and true or false
@@ -163,7 +168,7 @@ function string.escapedpattern(str,simple)
 end
 
 function string.topattern(str,lowercase,strict)
-    if str=="" or type(str) ~= "string" then
+    if str == "" or type(str) ~= "string" then
         return ".*"
     elseif strict then
         str = lpegmatch(pattern_c,str)
@@ -177,6 +182,7 @@ function string.topattern(str,lowercase,strict)
     end
 end
 
+-- print(string.escapedpattern("abc*234",true))
 -- print(string.escapedpattern("12+34*.tex",false))
 -- print(string.escapedpattern("12+34*.tex",true))
 -- print(string.topattern     ("12+34*.tex",false,false))
@@ -211,3 +217,24 @@ end
 
 string.quote   = string.quoted
 string.unquote = string.unquoted
+
+-- new
+
+if not string.bytetable then
+
+    local limit = 5000 -- we can go to 8000 in luajit and much higher in lua if needed
+
+    function string.bytetable(str)
+        local n = #str
+        if n > limit then
+            local t = { byte(str,1,limit) }
+            for i=limit+1,n do
+                t[i] = byte(str,i)
+            end
+            return t
+        else
+            return { byte(str,1,n) }
+        end
+    end
+
+end