Names

• Syntax:

  Alphanumeric, !, ?:	freddy12, prime?, update!
  Arbitrary:	_.entry, _if, _12
  Specific others:	0, 1, <, +, =, ..

• Special operators:

  a + b     <=>    (+)(a,b)
  
  + == (a: R, b: R): R +-> ...
  
  map(+, l)
  

• Certain syntaxes correspond to particular applications.

  [a,b,c]    --  bracket(a,b,c)
  a i := v   --  set!(a,i,v)