- Expose `read`, `read_str`, and `eval` in Python
- Add string evaluation example to interop section of docs
- Add test for `eval`
- Explain `eof` keyword argument in `read` docstring
The implementation of `hy.core.language.exec` draws code from the `exec_` function in commit f574c7be6ebc80041ef58ca29588f310248ebed4 of the library Six, which is copyright 2010–2017 Benjamin Peterson and licensed under the Expat license.
It was missing quotes around "Tuukka". Output from hy to confirm everything's good:
```clojure
hy unknown using CPython(default) 3.6.1 on Linux
=> (print "Hello there," "Tuukka")
Hello there, Tuukka
```
This is no longer necessary now that `defn` always produces a `FunctionDef`.
To compensate, I've made small edits to two contrib modules and reverted a small test change.
I was following along and noticed that it wasn't actually explained how to _use_ the object we just made. I include both the `setv` style of writing the Hy as we've been using in the rest of the docs up to this point and a more LISP-y style use of the object.
* Remove uses of `car` and `cdr` in /hy
* Remove uses of `car` and `cdr` in quote tests
* Remove `car` and `cdr` in favor of `first` and `rest`
I beefed up the documentation and tests for `first` and `rest` while I was at it.
I defined `car` and `cdr` in native_tests.cons so the tests read a bit more naturally.
* 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
