2023-04-26 23:31:00

1 files changed, 18 insertions, 0 deletions

diff --git a/tex/context/base/mkxl/syst-lua.lmt b/tex/context/base/mkxl/syst-lua.lmt
index d8e06d4fd..0f80f57d3 100644
--- a/tex/context/base/mkxl/syst-lua.lmt
+++ b/tex/context/base/mkxl/syst-lua.lmt
@@ -58,6 +58,9 @@ local ctx_secondoftwoarguments = context.secondoftwoarguments
 local ctx_firstofoneargument   = context.firstofoneargument
 local ctx_gobbleoneargument    = context.gobbleoneargument
 
+local values                   = tokens.values
+local boolean_code             = values.boolean
+
 implement { -- will be overloaded later
     name      = "writestatus",
     arguments = "2 arguments",
@@ -309,6 +312,21 @@ end
 
 do
 
+    interfaces.implement {
+        name      = "iflua",
+        public    = true,
+        usage     = "condition",
+        arguments = "string",
+        actions   = function(s)
+            local c = load("return(" .. s .. ")")
+            return boolean_code, (c and c()) and true or false
+        end,
+    }
+
+end
+
+do
+
     -- This is some 20% slower than native but we only provide this for compatibility
     -- reasons so we don't care that much about it. Eventually we can drop the built-in
     -- method.