Hy Files

Removals

• doc has been removed. Use (help (get-macro foo)) or (help (get-macro :reader foo)) instead.
• delmacro has been removed. Use (eval-when-compile (del (get _hy_macros (hy.mangle "foo")))) instead.
• hy.reserved has been removed. Use (.keys (builtins._hy_macros)) or Python's built-in keyword module instead.
• The environment variables HY_DEBUG and HY_FILTER_INTERNAL_ERRORS have been replaced with HY_SHOW_INTERNAL_ERRORS.

Other Breaking Changes

• defmacro and require can now define macros locally instead of only module-wide.
• When a macro is require\d from another module, that module is no longer implicitly included when checking for further macros in the expansion.
• hy.M has been renamed to hy.I.
• hy.eval has been overhauled to be more like Python's eval. It also has a new parameter macros.
• hy.macroexpand and hy.macroexpand-1 have been overhauled and generalized to include more of the features of hy.eval.
• hy now only implicitly launches a REPL if standard input is a TTY.
• hy -i has been overhauled to work as a flag like python3 -i.
• hy2py now requires -m to specify modules, and uses the same sys.path rules as Python when parsing a module vs a standalone script.
• New macro deftype.
• New macro get-macro.
• New macro local-macros.

New Features

• New syntax (hy.R.aaa/bbb.m …) for calling the macro m from the module aaa.bbb without bringing m or aaa.bbb into scope.
• nonlocal now also works for globally defined names.
• defn, defn/a, and defclass now support type parameters.
• HyReader now has an optional parameter to install existing reader macros from the calling module.
• New pragma warn-on-core-shadow.

Misc. Improvements

• Some syntax errors raised by core macros now have more informative messages.
• Logical operators now compile to simpler Python code in some cases.

Bug Fixes

• Implicit returns are now disabled in async generators.
• Fixed parsing of infinite and NaN imaginary literals with an uppercase "J".
• Double quotes inside of bracketed f-strings are now properly handled.
• Fixed incomplete recognition of macro calls with a unary dotted head like ((. defn) f []).
• ~@ #* now produces a syntax error instead of a nonsensical result.
• nonlocal now works for top-level let-bound names.
• require now warns when you shadow a core macro, like defmacro already did.
• Fixed hy.eval failing on defreader or require forms that install a new reader.
• The parameter result-ok that was mistakenly included in the signature of hy.macroexpand is now gone.
• hy -i with a filename now skips shebang lines.