

precise, logical types
term  description  Python type  Python expressions* 
primitive types 
boolean   int  1, 0, 1==0 
integer   int,long  0, 1, 2, 1 
floating point   float  2.718, 1.0 
string   string  "3 is the best number!" 
none  trivial type with just 1 value  None  None 
void  type with no values  None  mylist.append(123) 
the indiscriminate type    input: function from string to action returning the indiscriminate type 
derived types 
tuple of    ("hello", "my", "name", "is", "Phil", "."): tuple of string (11, 16, 18, 50, 52): tuple of integer 
list of    ["hello", "my", "name", "is", "Phil", "."]: list of string [11, 16, 18, 50, 52]: list of integer 
function from to    string.atoi: function from string to integer
car: for all t, function from list of t to t 
action returning    putnewline: action returning the trivial type
random.choice: for all e, function from (list of e) to action returning e 
and    subst: for all t, function from (t and t and (list of t)) to (list of t) 
or    talky: function from the indiscriminate type to (boolean or the trivial type) 
quantified types 
for all typeparameter,    cons: for all t, function from (t and (list of t)) to (list of t) 
*: some of the later examples are of Scheme functions rather than Python.
