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Comment by jasongrout | Hacker News Reader

I see the docs mention that these only work when importing modules. The dev version of IPython lets you transform the AST of code that is typed in the REPL. It would be really cool to see an IPython AST transformer based on this. Here is an example from the test files in IPython: https://github.com/ipython/ipython/blob/master/IPython/core/...

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Yep, there's an issue for that! https://github.com/lihaoyi/macropy/issues/14

I've also gotten a basic implementation working in the CPython REPL, which requires you to run a function `macro_repl()` before you can use them. A Macro powered REPL would be super cool!

MacroPy now works with the CPython REPL:

    PS C:\Dropbox\Workspace\6.945\Project> python
    Python 2.7 (r27:82525, Jul  4 2010, 07:43:08) [MSC v.1500 64 bit (AMD64)] on win32
    Type "help", "copyright", "credits" or "license" for more information.
    >>> import macropy.core.macros
    0=[]=====> MacroPy Enabled <=====[]=0
    >>> from macropy.macros2.tracing import macros, trace
    >>> trace%[x*2 for x in range(3)]
    range(3) -> [0, 1, 2]
    (x * 2) -> 0
    (x * 2) -> 2
    (x * 2) -> 4
    [(x * 2) for x in range(3)] -> [0, 2, 4]
    [0, 2, 4]

It's somewhat hacky, but it seems to work pretty well. I went through the examples and most of them work perfectly in the REPL, except for those whose have blank-lines-in-class-def confuse it

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