Scheme/Procedures: Difference between revisions

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where <expressions> is one or more, well, expressions. Only the last expression's value is returned.<br />
where <expressions> is one or more, well, expressions. Only the last expression's value is returned.<br />
<args> is your variable definitions, which can take the following forms:
<args> is your variable definitions, which can take the following forms:
* '''var''' - all arguments are put into this single variable.
* '''var''' - all arguments are put into this single variable (as a list.)
* '''(var[1] var[2] ... )''' - specifies a fixed number of arguments.
* '''(var[1] var[2] ... )''' - specifies a fixed number of arguments.
* '''(var[1] var[2] ... . var[n])''' - a space-delimited period before the final argument specifies the remaining args (if any) to be put into a list under that variable.
* '''(var[1] var[2] ... . var[n])''' - a space-delimited period before the final argument specifies the remaining args (if any) to be put into a list under that variable.
<br />
<br />
== Lexical Scoping ==
== Lexical Scoping ==
=== fluid-let ===
=== fluid-let ===

Revision as of 13:06, 3 April 2011

Lambdas

  • Can also be viewed as anonymous procedures.
  • Has the following syntax:
(lambda <args> <expressions>)

where <expressions> is one or more, well, expressions. Only the last expression's value is returned.
<args> is your variable definitions, which can take the following forms:

  • var - all arguments are put into this single variable (as a list.)
  • (var[1] var[2] ... ) - specifies a fixed number of arguments.
  • (var[1] var[2] ... . var[n]) - a space-delimited period before the final argument specifies the remaining args (if any) to be put into a list under that variable.


Lexical Scoping

fluid-let

Modifies existing global variables instead of introducing new lexical ones. Values are reset at the end of the expression.

Iteration

do

(do
  ((<var> <init> <step>) ... )
   (<test> <expression>)
   (<command> ... ))