Thank you Guys!
I think I get the point now - I will re-implement the statement as follows:
ifClause : 'if' LRND ifCond=rightExpr RRND ifBlock=block
;
ifExpr : ifClause ('else' ifClause)* ('else' elseBlock=block)?
;
does it look reasonable to you as above?
On Thu, Sep 2, 2010 at 1:52 PM, Loring Craymer <[email protected]> wrote:
> The problem is that you are considering 'else if' as a single token instead
> of
> thinking of the second 'if' as being part of its own statement. Just
> delete the
> 'else if' part of your ifExpr production and make sure that block can be an
> ifExpr. That is,
>
> if (cond1) block1
> else if (cond2) block2
> else block3
>
> is interpreted as
>
> if (cond) block1
> else { if (cond2) block2
> else block3
> }
>
> which, you should find, is what you really want.
>
> --Loring
>
>
>
>
>
> ----- Original Message ----
> > From: st3 <[email protected]>
> > To: [email protected]
> > Sent: Thu, September 2, 2010 9:45:54 AM
> > Subject: [antlr-interest] if/else if/else vs. if/elif/else
> >
> >
> > Hi,
> >
> > I have defined a simple if/else if/else rule (below):
> >
> > ifExpr : 'if' LRND ifCond=rightExpr RRND ifBlock=block
> > ('else if' LRND elifCond+=rightExpr RRND elifBlock+=block)*
> > ('else' elseBlock=block)?
> >
> > this throws the following error:
> >
> > mismatched character '{' expecting 'i'
> > extraneous input '}' expecting 'return '
> >
> > I can solve it by changing 'else if' to 'elif' - as clearly 'else if'
> and
> > 'else' are confusing the lexer/parser.
> >
> > However, I was hoping to have the easer-to-read 'else if'.
> >
> > Can someone suggest how I can accomplish that?
> >
> > I tried the syntactic predicate ('else if')=> - but that did not work.
> >
> > Thank you!
> > --
> > View this message in context:
> >
> http://antlr.1301665.n2.nabble.com/if-else-if-else-vs-if-elif-else-tp5491890p5491890.html
> >
> > Sent from the ANTLR mailing list archive at Nabble.com.
> >
> > List: http://www.antlr.org/mailman/listinfo/antlr-interest
> > Unsubscribe:
> >http://www.antlr.org/mailman/options/antlr-interest/your-email-address
> >
>
>
>
>
>
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