void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
Hello BCS,
void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
(mixin("s")) = 5;
Given that the above works, it looks like the parser prematurely commits
to a mixin declaration when it finds "mixin (" at function scope.
Unless someone spots a flaw in this, I'll post a bug.
BCS escribió:
Hello BCS,
void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
(mixin("s")) = 5;
Given that the above works, it looks like the parser prematurely commits
to a mixin declaration when it finds "mixin (" at function scope.
Unless someone spots a flaw in this, I'll post a bug.
Yes, at that point the parser is parsing statements, so if it finds a
"mixin(...)" it turns it into a statement.
I'm thinking about how to fix this. I think the parser should peek the
next token after the closing parenthesis. If it's a semicolon, then
treat it as a statement-mixin. Else, just invoke parseAssignExp and
create a new ExpStatement.
I modified this in Descent and it seems to work. :-)
Here's the code (in Java, but the idea is simple to translate to C++):
// inside Parser::parseStatement
case TOKmixin: {
Dsymbol d;
t = peek(token);
if (t.value == TOKlparen)
{
if (peekPastParen(t).value != TOKsemicolon) {
Expression e = parseAssignExp();
s = new ExpStatement(loc(), e);
} else {
// mixin(string)
nextToken();
check(TOKlparen);
Expression e = parseAssignExp();
check(TOKrparen);
check(TOKsemicolon);
s = newCompileStatement(loc(), e);
}
break;
} else {
d = parseMixin();
s = newDeclarationStatement(loc(), d);
break;
}
}
Hello Ary,
BCS escribió:
Hello BCS,
void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
Given that the above works, it looks like the parser prematurely
commits to a mixin declaration when it finds "mixin (" at function
scope.
Unless someone spots a flaw in this, I'll post a bug.
"mixin(...)" it turns it into a statement.
http://d.puremagic.com/issues/show_bug.cgi?id=3073
Hope you don't mind me quoting you.
BCS escribió:
Hello Ary,
BCS escribió:
Hello BCS,
void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
Given that the above works, it looks like the parser prematurely
commits to a mixin declaration when it finds "mixin (" at function
scope.
Unless someone spots a flaw in this, I'll post a bug.
"mixin(...)" it turns it into a statement.
http://d.puremagic.com/issues/show_bug.cgi?id=3073
Hope you don't mind me quoting you.
Not at all!
But later when I went to sleep I thought about that a little more, and
look at this:
1. mixin("int x = 2;");
2. mixin("x = 2");
The first should be treated as a MixinStatement, because it ends with a
semicolon. The second should be treated as a MixinExpression, because it
doesn't end with a semicolon (and it's a perfectly valid expression,
it's an assign expression). But according to my patch it'll be treated
as a statement and it'll fail.
Now this:
3. mixin("int x = 2");
is neither of them.
You can only deduce that information if you can extract the contents of
the mixin, paste it in the source file and treat the whole line as a
statement, and you'd get things right. But now all of those lines can be:
mixin(secret());
and now you don't know, you'll have to wait for semantic anlaysis to
know that, but then it's too late.
But I think my patch is reasonable because it allows you to do more
things than before, it's backwards compatible and also you'd almost
never do number 2 but instead use number 1.
BCS wrote:
void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
mixin *expression*
(4+3) = 5;
hasen wrote:
BCS wrote:
void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
mixin *expression*
(4+3) = 5;
Oh, never mind,
AssignExpression can be of the form:
ConditionalExpression = AssignExpression
my bad.
Hello hasen,
hasen wrote:
BCS wrote:
void main()
{
int s;
mixin("s") = 5;
}
-----
Line 4: found '=' when expecting ';'
http://www.digitalmars.com/d/1.0/expression.html#MixinExpression
(4+3) = 5;
AssignExpression can be of the form:
ConditionalExpression = AssignExpression
my bad.
Irony: I wrote a lib that abuses the grammer to allow exactly that kind of
syntax <g>
http://www.dsource.org/projects/scrapple/browser/trunk/backmath
C & C++
DMDScript
Ary Borenszweig <ary esperanto.org.ar> 