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Comment by samth | Hacker News Reader

No, macros and eval are quite different. You can see this for example in Python or JavaScript, which have eval but not macros.

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You can make macros in Python: https://github.com/lihaoyi/macropy (note that that project was started for a class taught by Sussman)

There's also a PEP to make them first-class: https://peps.python.org/pep-0638/

That's a different meaning of first-class from Strachey's definition of a first-class citizen[1] - ie, one that can be passed as an argument, returned from a function, or assigned to a variable.

Syntactic macros are still second-class, like Lisp macros, but an improvement over text-replacement style macros.

For something macro-like which is first-class, there are fexprs[2] and operatives (from Kernel[3]) - these receive their operands verbatim, like macros, so they don't require quotation if we want to suppress evaluation. fexprs/Operatives can be passed around like any other value at runtime.

[1]:https://en.wikipedia.org/wiki/First-class_citizen

[2]:https://en.wikipedia.org/wiki/Fexpr

[3]:https://web.cs.wpi.edu/~jshutt/kernel.html

Stratchey defined "first-class objects". This was by analogy with "first-class citizens" in a legal/political sense, since they are treated just as well as any other object and have no additional limitations. If we extend the analogy to syntax then I think it's clear enough that it means that it is a piece of syntax which is treated the same as any other and does not require special treatment or impose additional restrictions.

Thank you for the clarification and the additional information, I think having macros as first-class objects is a cool (but separate) idea.

They aren't that different. Fexprs are essentially additional eval cases.

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