On Wednesday, 11 September 2013 at 19:29:48 UTC, Jonathan M Davis
wrote:
On Wednesday, September 11, 2013 19:17:26 Manfred Nowak wrote:
Walter Bright wrote:
> Parsing D requires arbitrary lookahead.
Why---and since which version?
IIRC, it's at least partially cause by the .. token. You have
to look ahead to
figure out whether it's .. or a floating point literal. There
may be other cases
as well, but that particular one was actually complained about
by Robert
Schadek in his talk at dconf 2013.
- Jonathan M Davis
Yeah. D requires lookahead in both lexing and parsing. Some
examples:
* String literals such as q{}
* If statements need to determine the difference between if
(expression) and if (type identifier = expression)
* Determining if something is a lamba expression or a function
literal expression
* Determining if something is a declaration or a statement or an
expression.
* Differentiating between (type).identifier and a lambda
expression
* Differentiating between a type and an expression inside a
typeid expression
* Differentiating between associative array key type and tuple
slices in type suffixes
