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(librep.info)Notation

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Enter node , (file) or (file)node

Notation
--------

   Wherever an example of evaluating a Lisp form is shown it will be
formatted like this,

     (+ 1 2)
         => 3

The glyph `=>' is used to show the computed value of a form. (1)

   When two forms are shown as being exactly equivalent to one another
the glyph `==' is used, for example,

     (car some-variable) == (nth 0 some-variable)

   Evaluating some forms result in an error being signalled, this is
denoted by the `error-->' glyph.

     (open-file "/tmp/foo" 'read)
         error--> File error: No such file or directory, /tmp/foo

   ---------- Footnotes ----------

   (1) In this case the list `(+ 1 2)' (i.e. the list containing three
elements, the symbol `+' and, the numbers 1 and 2), represents a
function application. The first element in the list is the name of the
function to be called, all other elements are the arguments to apply to
it. Since the `+' function adds a series of numbers, the above function
call is actually performing the computation `1 + 2'.