DenkzeitWiki

Lisp Macros

• Lecture Notes: Macros

Lisp macros are a full-fledged code-generation system, while C #define macros are simple string substitutions.

• code that creates code
• AbstractSyntaxTrees
• http://osteele.com/archives/2004/09/becoming-lisp
  
• Macros and Closures

In other words, with macros you can tailor the language to do exactly what you want to do, in a single command. Without macros the best you can do is neatly arrange stock language constructs to map more or less closely to what you are trying to do.

Macros are just another way to write something once, and use it over and over again.[1]

• Python, XML. and now .Net?, copious .Net CodeDom?. String-concatenation is better... ;-)
  
  
• Understanding Syntactic Macros

Macros are like metaprogramming at compile time (or interpretation-time—Lisp lets you decide if you want to compile the code first or not).

• http://programmers.stackexchange.com/questions/50758/c-dev-ive-tried-lisps-but-i-dont-get-it/50762#50762
  
  
• Lisp development with macros faster than Python development?..

 -> Lisp macros allow the abstraction of special forms.

• Why you want macros (even if you don't know it yet) by Chouser?

I don't like macros any more. I'm right. Everyone who disagrees with me is wrong. End of story. [2]

• [IWE] Why Lisp macros are cool, a Perl perspective
  
• THE POWER OF LISP MACROS
  
• http://nklein.com/wp-content/uploads/2009/07/MeetTheMacro.pdf

• The Adventures of a Pythonista in Schemeland/25
  
  
• Ask HN: Are macros still an enormous edge in the power of a language?
  • specifically: http://news.ycombinator.com/item?id=645338
    • http://carcaddar.blogspot.com/2009/06/why-your-language-needs-macros.html

• http://stackoverflow.com/questions/267862/what-makes-lisp-macros-so-special
  
  
• The issue of macro is that it is, by itself, not a power. It's like how knife by...
  • GrowingALanguage
    

• Building Little Languages with Macros

• Ask HN: Are macros still an enormous edge in the power of a language?
  
• An Introduction to Lisp Macros, by David Nolen

Preprocessors

1. Lexical (C, C++, ...)
2. Syntactical (Lisp, OCaml, ...)
   1. AbstractSyntaxTrees

Macros and Functions

• http://www.delorie.com/gnu/docs/elisp-manual-21/elisp_176.html

1. Parameters of a macro don't get evaluated before being passed to the macro
2. The macro is expanded to lisp-forms. Which are then evaluated.

The consensus on the ll1 thread seemed to be that macros and functions aren't very different, except that macros can be more convenient--until Steele came up with a couple macros that depended on having access to the lexical form of the code body. Macros that symbolically differentiated the function being computed, for example.[3]

• Macros Make Me Mad