hy/docs/contrib/hy_repr.rst

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==================
Hy representations
==================
.. versionadded:: 0.13.0
``hy.contrib.hy-repr`` is a module containing a single function.
To import it, say::
(import [hy.contrib.hy-repr [hy-repr]])
To make the Hy REPL use it for output, invoke Hy like so::
$ hy --repl-output-fn=hy.contrib.hy-repr.hy-repr
.. _hy-repr-fn:
hy-repr
-------
Usage: ``(hy-repr x)``
This function is Hy's equivalent of Python's built-in ``repr``.
It returns a string representing the input object in Hy syntax.
.. code-block:: hy
=> (hy-repr [1 2 3])
'[1 2 3]'
=> (repr [1 2 3])
'[1, 2, 3]'
If the input object has a method ``__hy-repr__``, it will be called
instead of doing anything else.
.. code-block:: hy
=> (defclass C [list] [__hy-repr__ (fn [self] "cuddles")])
=> (hy-repr (C))
'cuddles'
When ``hy-repr`` doesn't know how to handle its input, it falls back
on ``repr``.
Like ``repr`` in Python, ``hy-repr`` can round-trip many kinds of
values. Round-tripping implies that given an object ``x``,
``(eval (read-str (hy-repr x)))`` returns ``x``, or at least a value
that's equal to ``x``.