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~cslab/bin/cs257-scheme
~cslab/bin/cs257-handin
~cslab/bin/emacs

ln -s ~cslab/.emacs ~/.emacs

Language manual, implementation manual:
netscape http://www.unm.edu/~cslab/plt/...

expressions

comment syntax
expression syntax
generality.  variable numbers of arguments.
datatypes: numbers and symbols
 extended precision (bignums)
 rationals
 exact & inexact

various builtin functions (see R4RS)

   essential procedure: number? obj
   essential procedure: complex? obj
   essential procedure: real? obj
   essential procedure: rational? obj
   essential procedure: integer? obj


   essential procedure: exact? z
   essential procedure: inexact? z

   essential procedure: = z1 z2 z3 ...
   essential procedure: < x1 x2 x3 ...
   essential procedure: > x1 x2 x3 ...
   essential procedure: <= x1 x2 x3 ...
   essential procedure: >= x1 x2 x3 ...

   essential procedure: zero? z
   essential procedure: positive? x
   essential procedure: negative? x
   essential procedure: odd? n
   essential procedure: even? n

   essential procedure: max x1 x2 ...
   essential procedure: min x1 x2 ...

   essential procedure: + z1 ...
   essential procedure: * z1 ...

   essential procedure: - z1 z2
   essential procedure: - z
   procedure: - z1 z2 ...

   essential procedure: / z1 z2
   essential procedure: / z
   procedure: / z1 z2 ...

   essential procedure: abs x

   essential procedure: quotient n1 n2
   essential procedure: remainder n1 n2
   essential procedure: modulo n1 n2

   essential procedure: gcd n1 ...
   essential procedure: lcm n1 ...

   procedure: numerator q
   procedure: denominator q

   essential procedure: floor x
   essential procedure: ceiling x
   essential procedure: truncate x
   essential procedure: round x

   procedure: rationalize x y
                            
   procedure: exp z
   procedure: log z
   procedure: sin z
   procedure: cos z
   procedure: tan z
   procedure: asin z
   procedure: acos z
   procedure: atan z
   procedure: atan y x
   procedure: sqrt z

   Returns the principal square root of z. The result will have either
   positive real part, or zero real part and non-negative imaginary part.

   procedure: expt z1 z2
   
   procedure: make-rectangular x1 x2
   procedure: make-polar x3 x4

   procedure: real-part z   
   procedure: imag-part z

   procedure: magnitude z
   procedure: angle z

   procedure: exact->inexact z
   procedure: inexact->exact z

true and false; if
IF is a "special form" like DEFINE and LAMBDA