* with-decorator: Allow a `setv` form as the form to be decorated
This feature is of dubious value by itself, but it's necessary to allow `defn` to create a lambda instead of a `def`.
* Make `fn` work the same as `lambda`
That is, allow it to generate a `lambda` instead of a `def` statement if the function body is just an expression.
I've removed two uses of with_decorator in hy.compiler because they'd require adding another case to HyASTCompiler.compile_decorate_expression and they have no ultimate effect, anyway.
In a few tests, I've added a meaningless statement in `fn` bodies to force generation of a `def`.
I've removed `test_fn_compiler_empty_function` rather than rewrite it because it seems like a pain to maintain and not very useful.
* Remove `lambda`, now that `fn` does the same thing
Per the straw poll in #908, as an alternative to #1147.
Now you must use `True`, `False`, and `None`, as in Python. Or just assign `true` to `True`, etc.; the old synonyms aren't reserved words anymore.
Give `require` the same features as `import`
You can now do (require foo), (require [foo [a b c]]), (require [foo [*]]), and (require [foo :as bar]). The first and last forms get you macros named foo.a, foo.b, etc. or bar.a, bar.b, etc., respectively. The second form only gets the macros in the list.
Implements #1118 and perhaps partly addresses #277.
N.B. The new meaning of (require foo) will cause all existing code that uses macros to break. Simply replace these forms with (require [foo [*]]) to get your code working again.
There's a bit of a hack involved in the forms (require foo) or (require [foo :as bar]). When you call (foo.a ...) or (bar.a ...), Hy doesn't actually look inside modules. Instead, these (require ...) forms give the macros names that have periods in them, which happens to work fine with the way Hy finds and interprets macro calls.
* Make `require` syntax stricter and add tests
* Update documentation for `require`
* Documentation wording improvements
* Allow :as in `require` name lists
The `if` form now supports elif clauses.
It works like `cond` but without the implicit `do`.
The old `if` is now `if*`
variadic lif now supports "ellif" clauses.
Update if-no-waste compiler to use `if*` properly.
(Sometimes one character is all it takes.)
document if
reword truthiness
Comparison operators such as =, !=, <, >, <=, >= should support a
one-arity version too, and return true in those cases (except for !=,
which returns false).
This closes#949.
Reported-by: Matthew Egan Odendahl
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
This changes let to use a flat list of symbol-value pairs instead of a
vector of vectors. One side effect is that (let [[a 1] z]) is not
expressible now, and one will explicitly need to set a nil value for z,
such as: (let [a 1 z nil]).
Closes#713.
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
To allow classes to have methods that match built-in names, yet, still
disallow them outside of defclass, keep an internal state whether
builtins are allowed in the current context.
By default, this is false. But defclass will set it to True when it
compiles its body, and set it back to the previous value when it's done
with that. We need to set back to the previous value to allow nested
defclasses to work properly.
This closes#783.
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
Strip the \ufdd0 prefix from the keyword argument before turning it into
a string: the same representation the user entered looks better, and is
printable too, thus Python2 doesn't choke on it.
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
Some valid-looking list comprehensions, such as (genexpr x []) can crash
Python 2.7. The AST we generate from these cannot be expressed in
Python, but were valid in Hy.
Added two guards to guard against this, so we raise an error instead of
crashing Python.
Closes#572, #591 and #634.
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
When trying to setv a callable, raise an error instead of showing the
user an incredibly ugly backtrace. Closes#532.
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
In case for doesn't get a body, raise the appropriate, descriptive error
instead of an IndexOutOfBounds one. Also updated the failing test case.
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
Much like how `can_compile` returns the compilation result, which some
tests make use of, it may be useful for for `cant_compile` to return the
exception object that it caught, for more specific assertions.
jcrocholl/pep8 (used by flake8, used in Hy's continuous integration
builds) introduced an imports-at-top-of-file check in 1.6.0 and a
line-breaks-around-binary-operators check in 1.6.2. This commit makes
nonfunctional changes to bring the Hy codebase in compliance with this
tool, fixing #764.
This also breaks out the PY3 only tests into their own file. We need to do this because raise from is a syntax error in PY2, so we can't rely on the previous hack of catching a HyCompileError - it would compile fine through Hy and then be a syntax error in Python.
This version is much simpler.
At the point that the exception is raised, we don't have access to
the actual source, just the current expression. but as the
exception percolates up, we can intercept it, add the source and
the re-raise it.
Then at the final point, in the cmdline handler, we can choose to
let the entire traceback print, or just the simpler, direct error
message.
And even with the full traceback, the last bit is nicely formatted
just like the shorter, simpler message.
The error message is colored if clint is installed, but to avoid
yet another dependency, you get monochrome without clint.
I'm sure there is a better way to do the markup, the current method
is kludgy but works.
I wish there was more shared code between HyTypeError and LexException
but they are kind of different in some fundamental ways.
This doesn't work (yet) with runtime errors generated from Python,
like NameError, but I have a method that can catch NameError and turn it
into a more pleasing output.
Finally, there is no obvious way to raise HyTypeError from pure Hy code,
so methods in core/language.hy throw ugly TypeError/ValueError.
