Commit Graph

9 Commits

Author SHA1 Message Date
Chris Lattner
468ead25a6 allow 'var' and 'let' to appear in patterns (not just matching patterns).
This allows them to appear in argument lists of functions, enabling behavior
like this:

func test_arguments(a : Int, var b : Int, let c : Int) {
  a = 1  // ok (for now).
  b = 2  // ok.
  c = 3  // expected-error {{cannot assign to the result of this expression}}
}



Swift SVN r11746
2013-12-30 21:48:06 +00:00
Joe Groff
e109124186 Replace 'union' keyword with 'enum'.
This only touches the compiler and tests. Doc updates to follow.

Swift SVN r8478
2013-09-20 01:33:14 +00:00
Jordan Rose
674a03b085 Replace "oneof" with "union"...everywhere.
We haven't fully updated references to union cases, and enums still are not
their own thing yet, but "oneof" is gone. Long live "union"!

Swift SVN r6783
2013-07-31 21:33:33 +00:00
Joe Groff
3b21e6a201 Add a OneOfElementPattern AST node type.
Add a node for references to oneof cases in patterns. No user-facing functionality change yet.

Swift SVN r6239
2013-07-13 01:21:31 +00:00
Joe Groff
53221db84c AST: Add 'VarPattern' node.
We decided to go with 'var' as a distributive pattern introducer which applies to bare identifiers within the subpattern. For example, 'var (a, b)' and '(var a, var b)' would be equivalent patterns. To model this, give 'var' its own AST node with a subpattern and remove the introducer loc from NamedPattern.

Swift SVN r5824
2013-06-26 23:01:47 +00:00
Joe Groff
e460a01af6 Remove the 'UnresolvedCallPattern' I stubbed out.
I talked to John about parsing patterns today, and because of the magnitude of name-lookup-dependent ambiguities between patterns and expressions, we agreed that at least for a first-pass implementation it makes sense to parse patterns as extensions of the expr grammar and charge name binding with distinguishing patterns from expressions. This gets us out of needing the concept of an "unresolved pattern", at least in the short term.

Swift SVN r5808
2013-06-26 04:23:47 +00:00
Joe Groff
7ba95cfd26 Add AST nodes for refutable patterns.
Introduce Pattern subclasses for the 'is T', 'T(<pattern>)', and '<expr>' pattern syntaxes we'll be introducing for pattern-matching "switch" statements. Also add an 'UnresolvedCalLPattern' to act as an intermediate for name lookup to resolve to a nominal type, oneof element, or function call expression pattern. Since we'll need to be able to rewrite patterns like we do expressions, add setters to AST nodes that contain references to subpatterns. Implement some basic walking logic in places we search patterns for var decls, but punt on any more complex type-checking or SILGen derived from these nodes until we actually use them.

Swift SVN r5780
2013-06-24 17:17:34 +00:00
John McCall
16f8b2e656 Revise the language design for function argument clause syntax.
A function argument clause is now one or more patterns (which
must be parenthesized and explicitly type all positions) not
separated by arrows;  the first arrow then separates off the
return type.

Revisions to language reference forthcoming.



Swift SVN r1099
2012-01-26 01:25:26 +00:00
John McCall
ecb7bbc790 Basic ASTs for pattern-matching. We're going to generate
these for FuncExpr signatures.



Swift SVN r1095
2012-01-24 22:27:06 +00:00