Add meta-variable keywords high-lighting

queries/highlights.scm

@@ -41,6 +41,12 @@
   "type"
   "var"
   "while"
+
+  "_cast"
+  "_chunks"
+  "_exp"
+  "_lvalue"
+  "_namety"
 ] @keyword
 ; }}}
 

test/highlight/meta-variables.tig

@@ -0,0 +1,13 @@
+let
+  _chunks(42)
+  /* <- keyword */
+
+in
+  _lvalue(12) : _namety(42) := _cast("I'm So Meta Even This Acronym", string);
+  /* <- keyword */
+  /*            ^ keyword */
+  /*                           ^ keyword */
+
+  _exp(42)
+  /* <- keyword */
+end