# New Ticket Created by Ron Schmidt
# Please include the string: [perl #55594]
# in the subject line of all future correspondence about this issue.
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=55594 >
Perl 5 allows empty semicolon terminated statements. perl6 currently
allows for empty closures but treats a semicolon that follows nothing or
whitespace as a syntax error. The attached patch to grammar.pg provides
a fix for this discrepancy between perl 5 and perl 6. Also attached is
an attempt at a test suite for some statement termination cases.
The patch is small and passes "make fulltest" under ubuntu and "make
spectest", as well as the parts of "make test" in the perl6 directory,
under cygwin. Modifying statementlist this way does not appear to be
the most elegant solution to the problem but approaches like
[<statement>?<.eat_terminator> ]* seemed to fail with relatively serious
errors.
The terminator.t test file is vaguely intended for the
t/spec/S04-statements/ directory.
Index: t/spectest_regression.data
===================================================================
--- t/spectest_regression.data (revision 28227)
+++ t/spectest_regression.data (working copy)
@@ -15,6 +15,7 @@
S03-operators/not.t # pure
S03-operators/relational.t # pure
S03-operators/true.t # pure
+S04-statements/terminator.t # pure
S04-statements/try.t
S04-statements/until.t # pure
S04-statements/while.t
Index: src/parser/grammar.pg
===================================================================
--- src/parser/grammar.pg (revision 28227)
+++ src/parser/grammar.pg (working copy)
@@ -151,8 +151,10 @@
rule statementlist {
- [<statement><.eat_terminator> ]*
- {*}
+ | [
+ || ';'
+ || <statement><.eat_terminator>
+ ]* {*}
}
## The eat_terminator detects when we're at a valid
use v6;
use Test;
plan 9;
# L<S04/"Statement parsing"/"statement termination">
# the 'empty statement' case responsible for the creation of this test file
eval_lives_ok(';', 'empty statement');
eval_lives_ok('my $x = 2', 'simple statement no semi');
eval_lives_ok('my $x =
9', 'simple statement on two lines no semi');
eval_lives_ok('my $x = 2;', 'simple statement with semi');
eval_lives_ok('{my $x = 2}', 'end of closure terminator');
eval_lives_ok('{my $x =
2;}', 'double terminator');
eval_lives_ok(';my $x = 2;{my $x = 2;;};', 'extra terminators');
eval_dies_ok('{my $x = 2;', 'open closure');
eval_dies_ok('my $x = ', 'incomplete expression');
