+@deffn {Directive} %code @{@var{code}@}
+@findex %code
+This is the unqualified form of the @code{%code} directive.
+It inserts @var{code} verbatim at the default location in the output.
+That default location is determined by the selected target language and/or
+parser skeleton.
+
+@cindex Prologue
+For the current C/C++ skeletons, the default location is the parser source code
+file after the usual contents of the parser header file.
+Thus, @code{%code} replaces the traditional Yacc prologue,
+@code{%@{@var{code}%@}}, for most purposes.
+For a detailed discussion, see @ref{Prologue Alternatives}.
+
+@comment For Java, the default location is inside the parser class.
+
+(Like all the Yacc prologue alternatives, this directive is experimental.
+More user feedback will help to determine whether it should become a permanent
+feature.)
+@end deffn
+
+@deffn {Directive} %code @var{qualifier} @{@var{code}@}
+This is the qualified form of the @code{%code} directive.
+If you need to specify location-sensitive verbatim @var{code} that does not
+belong at the default location selected by the unqualified @code{%code} form,
+use this form instead.
+
+@var{qualifier} identifies the purpose of @var{code} and thus the location(s)
+where Bison should generate it.
+Not all values of @var{qualifier} are available for all target languages:
+
+@itemize @bullet
+@findex %code requires
+@item requires
+
+@itemize @bullet
+@item Language(s): C, C++
+
+@item Purpose: This is the best place to write dependency code required for
+@code{YYSTYPE} and @code{YYLTYPE}.
+In other words, it's the best place to define types referenced in @code{%union}
+directives, and it's the best place to override Bison's default @code{YYSTYPE}
+and @code{YYLTYPE} definitions.
+
+@item Location(s): The parser header file and the parser source code file
+before the Bison-generated @code{YYSTYPE} and @code{YYLTYPE} definitions.
+@end itemize
+
+@item provides
+@findex %code provides
+
+@itemize @bullet
+@item Language(s): C, C++
+
+@item Purpose: This is the best place to write additional definitions and
+declarations that should be provided to other modules.
+
+@item Location(s): The parser header file and the parser source code file after
+the Bison-generated @code{YYSTYPE}, @code{YYLTYPE}, and token definitions.
+@end itemize
+
+@item top
+@findex %code top
+
+@itemize @bullet
+@item Language(s): C, C++
+
+@item Purpose: The unqualified @code{%code} or @code{%code requires} should
+usually be more appropriate than @code{%code top}.
+However, occasionally it is necessary to insert code much nearer the top of the
+parser source code file.
+For example:
+
+@smallexample
+%code top @{
+ #define _GNU_SOURCE
+ #include <stdio.h>
+@}
+@end smallexample
+
+@item Location(s): Near the top of the parser source code file.
+@end itemize
+@ignore
+@item imports
+@findex %code imports
+
+@itemize @bullet
+@item Language(s): Java
+
+@item Purpose: This is the best place to write Java import directives.
+
+@item Location(s): The parser Java file after any Java package directive and
+before any class definitions.
+@end itemize
+@end ignore
+@end itemize
+
+(Like all the Yacc prologue alternatives, this directive is experimental.
+More user feedback will help to determine whether it should become a permanent
+feature.)
+
+@cindex Prologue
+For a detailed discussion of how to use @code{%code} in place of the
+traditional Yacc prologue for C/C++, see @ref{Prologue Alternatives}.
+@end deffn
+
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