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docs/md/extensions.md

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+Extensions to core Prolog.			{#extensions}
+=========================
+
+YAP includes a number of extensions over the original Prolog
+language. Next, we discuss how to use the most important ones.
+
+  + @ref Rational_Trees
+
+  + @ref AttributedVariables
+
+  + @ref  DepthLimited
+
+  + @ref  Tabling
+
+  + @ref Threads
+
+  + @ref Profiling
+
+  + @ref YAPArrays
+
+  + @ref Parallelism