Version 0.9.5 Released#

Highlights of this release:

SYNTAX#

• New syntactic sugar "x?" and "x:=y" for reference reads and writes.
• Operators can be written in prefix form (or unapplied) using parentheses: "(+)" is equivalent to "lambda (a,b) = a+b".
• New "type" declaration for declaring algebraic data type constructors.
• Any combinator is allowed unparenthesized within if/then/else.
• Allow apostrophe in var names.
• Allow nested comments.
• Newline-sensitivity avoids ambiguity about where expressions end.

SEMANTICS#

• Equality operator "=" now obeys substitutability principle.
• New semantics for semicolon operator: in "a ; b", "b" runs only if "a" fails without publishing any values.
• Java fields can be accessed with the dot operator.

LIBRARY#

• Standard library organized, documented, and expanded with many more useful sites and definitions.
• Experimental support for "doc" tags ala javadoc, translated into docbook syntax by a special parser.

IMPLEMENTATION#

• Enforceable limits on recursive stack depth and logical threads.
• A closure only keeps variables used in the closure live, for garbage collection purposes.
• Definitions are organized into mutually-recursive groups to keep environments small and avoid false depenendencies on futures introduced by the pruning combinator.