These changes make the Hy REPL more closely follow `code.InteractiveConsole`'s
class interface and provide minimally intrusive traceback print-out filtering
via a context manager that temporarily alters `sys.excepthook`. In other words,
exception messages from the REPL will no longer show Hy internal
code (e.g. importer, compiler and parsing functions).
The boolean variable `hy.errors._hy_filter_internal_errors` dynamically
enables/disables trace filtering, and the env variable
`HY_FILTER_INTERNAL_ERRORS` can be used as the initial value.
This commit refactors the exception/error classes and their handling.
It also retains Hy source strings and their originating file information, when
available, all throughout the core parser and compiler functions.
As well, with these changes, calling code is no longer responsible for providing
source and file details to exceptions,
Closeshylang/hy#657.
These changes make `HyREPL` use a single `HyASTCompiler` instance, instead of
creating one every time a valid source string is processed.
This change avoids the unnecessary re-initiation of the standard library
`import` and `require` steps that currently occur within the module tracked by a
`HyREPL` instance.
Also, one can now pass an existing compiler instance to `hy_repl` and
`hy_compiler`.
Closeshylang/hy#1698.
Previously, when importing `hy` (and any of its sub-packages/modules), Hy source
compilation for `hy.core.language` was necessarily triggered. This, in turn,
would trigger compilation of the other standard library source files.
This commit removes that chain of events and allows the `hy` package to be
imported without any Hy compilation.
Furthermore, `read` and `read_str` are now implemented in Python and the Hy
standard library files now handle their own dependencies explicitly (i.e. they
`import` and/or `require` the other standard library files upon which they
depend).
The latter changes were necessary, because the automatically triggered
compilation of `hy.core.language` (and associated standard library files) was
serving--implicitly--as a means of producing bytecode in an order that just
happened to work for any compilation occurring afterward. This chain of
events/dependencies was extremely cryptic, brittle, and difficult to debug, and
these changes should help to remedy that.
Closeshylang/hy#1697.
Functions and variables relating to compilation and parsing have been moved to
`compiler.py` and `lex/__init__.py`, respectively. Those functions are
- `hy_parse` from `hy.importer` to `hy.lex`
- `hy_eval`, `ast_compile`, and `calling_module` from `hy.importer` to
`hy.compiler`
Closeshylang/hy#1695.
Python 3.x is patched in a way that integrates `.hy` source files into
Pythons default `importlib` machinery. In Python 2.7, a PEP-302 "importer"
and "loader" is implemented according to the standard `import` logic (via
`pkgutil` and later pure-Python `imp` package code).
In both cases, the entry-point for the loaders is through `sys.path_hooks` only.
As well, the import semantics have been updated all throughout to utilize
`importlib` and follow aspects of PEP-420. This, along with some light
patches, should allow for basic use of `runpy`, `py_compile` and `reload`.
In all cases, if a `.hy` file is shadowed by a `.py`, Hy will silently use
`.hy`.
Auto-promotion now occurs in only two cases: when we start the compiler and when we expand a macro. It's fully recursive so even a non-model nested in a model will be promoted.
This change fixes some regressions induced by the stricter type checks of the pattern-matching compiler.
_stdlib is a global variable, so core modules could use it, contrary to our intention, so long as they happened to be compiled after a non-core module. I've added a compiler attribute to track whether we can use _stdlib.
This fix exposed some cases where hy.core.shadow tried to use a core function, so I fixed those.
I've also added an `if not _stdlib` to `load_stdlib` so that we only bother to actually load _stdlib once.
Brandon T. Willard