In Swift the "in" keyword is really a form of punctuation, and highly
context specific punctuation at that. It never begins a statement, nor
does the grammar require it be statement keyword. The grammar also
doesn't use it outside of for-each loops, and its use within a for-each
loop is highly unambiguous.
Thanks to Chris for the performance related feedback. This improves the
performance of getter/setter parsing as well.
Swift SVN r3880
Given that we want semicolon statement separators to be optional,
literals can bump up right next to the previous statement at the moment:
'var x = y"hello".print()' is two statements right now, not one broken
expression being used to initialize to 'x'. This is unfortunate if we
ever want to support C++ style raw strings or otherwise have some back
pocket grammar tricks to implement type state or trivially unambiguous
generics.
Swift SVN r3871
Dave noted that he's trying to scrub the parser codebase of wishy-washy 'isAnyLParen' and 'isAnyLBrace' calls by consistently lexing opening bracket tokens correctly to begin with. Since currently only 'super' and 'constructor' need to be lexed like identifiers for expression syntax (and, in the future, 'this' and 'This' when those become keywords), mark them as a special kind of 'identifier keyword' in Tokens.def and roll back some of the changes I made to make parsing other decls support either token.
Swift SVN r3848
Opening brackets after a keyword have to lex as l_paren_call or l_square_subscript in order for expressions like 'super.constructor()' or 'super[i]' to parse. While we're here, let's move the keyword and punctuator list to a metaprogrammable Tokens.def header too. Update decl and stmt parsers to use 'isAnyLParen' so that, e.g., 'constructor(' and 'constructor (' both work as before.
Swift SVN r3846
The lexer now models tuples, patterns, subscripting, function calls, and
field access robustly. The output tokens are now better named as well:
l_paren and l_paren_call, and l_square and l_square_subscript. It
should be much more clear now which one to use. Also, the use of
l_paren or l_square will not arbitrarily flip flop if the token before
it is a keyword or if the token before it was the trailing ']' of an
attribute list. Similarly, tuples will always cause the lexer to produce
l_paren, regardless if the user typed '((x,y))' or '( (x,y))'.
When we someday add array literals, the right token is now naturally
falling out of the lexer.
Swift SVN r3840
'.' is an operator in order to make '..' work and perhaps someday '...'
work, but we shouldn't interpret '....' as '...' followed by '.'.
Swift SVN r3705
resulting token goes back through the lexer to get the appropriate
token kind. Thanks to Chris for spotting this.
Also, document the '<' and '>' splitting behavior in LangRef.
Swift SVN r2192
and use this information as cues in the language. Right now,
we do not accept things like "-- *i" because the prefix
operator is not correctly right-bound; instead you have to
write "--(*i)". I'm okay with that; I did add a specialized
diagnostic recognizing operator-binary in a place where we're
expecting a potential operator-prefix.
Swift SVN r2161
interesting character on failure as well as on success. Simplify the
code in Lexer::getEncodedStringLiteral since it cannot be called on a
string with an malformed interpolated expression.
Swift SVN r1758
e.g. "foo is \(i+j)". This implements rdar://11223686
Doug implemented all the hard parts of this. I ripped out support for nested string
literals (i.e. string literals within an interpolated string), which simplified the
approach and defined away some problems with his patch in progress. I plan a few refinements
on top of this basic patch.
Swift SVN r1738
Per discussion, this should probably be "no newline since the last
token", but that decision should be made simultaneously for ( and [.
Swift SVN r1461
This has the side-effect that you can't explicitly refer to an operator* with "swift.*", etc., but per discussion with Doug, that's probably okay.
Swift SVN r1443
