a68: implement GNU68-2026-001-short-of-symbol

This patch implements the GNU extension:

  GNU68-2026-001-brief-selection - Brief style for selection

which adds the preferred brief style for selection recommended by
Hansen in "ALGOL 68 Hardware Represenatation Recommendations"
published in the Algol Bulletin issue 42.

This extension is already listed in https://algol68-lang.org.

Signed-off-by: Jose E. Marchesi <jemarch@gnu.org>

gcc/algol68/ChangeLog

	* ga68.vw: Update formal grammar to express the GNU extension.
	* a68-parser.cc (a68_dont_mark_here): Likewise.
	* a68-parser-scanner.cc (SINGLE_QUOTE_CHAR): Define.
	(get_next_token): Recognize ' as QUOTE_SYMBOL.
	(tokenise_source): Acknowledge QUOTE_SYMBOL.
	* a68-parser-keywords.cc (a68_set_up_tables): Likewise.
	* a68-parser-bottom-up.cc (reduce_primary_parts): Adjust parser to
	brief form of selection.
	* a68-parser-attrs.def (QUOTE_SYMBOL): New attribute.
	* ga68.texi (Brief selection): New section.

gcc/testsuite/ChangeLog

	* algol68/compile/error-selector-1.a68: New test.
	* algol68/execute/selection-2.a68: Update test.
	* algol68/execute/selection-5.a68: Likewise.

0 files changed, 0 insertions, 0 deletions