Built-in Types and Operators

Operators and Precedence

Table 1-1 lists Python’s expression operators. Operators in the lower cells of this table have higher precedence (i.e., bind tighter) when used in mixed-operator expressions without parentheses.

Table 1-1. Expression operators and precedence

Operators

Description

lambda args: expr

Anonymous function maker

X or Y

Logical OR: Y is evaluated only if X is false

X and Y

Logical AND: Y is evaluated only if X is true

not X

Logical negation

X < Y, X <= Y, X > Y, 
X >= Y, X == Y, X <> Y, 
X != Y, X is Y, X is not Y, 
X in S, X not in S

Comparison operators,[a] equality operators, inequality operators, object identity tests, sequence membership

X | Y

Bitwise OR

X ^ Y

Bitwise exclusive OR

X & Y

Bitwise AND

X << Y, X >> Y

Shift X left, right by Y bits

X + Y, X—Y

Addition/concatenation, subtraction

X * Y, X % Y,
X / Y, X // Y

Multiply/repetition, remainder/format, division, floor division[b]

-X, +X, ~X, X**Y

Unary negation, identity, bitwise complement, power

X[i], X[i:j], 
X.attr, X(...)

Indexing, slicing, attribute references, function calls

(...), [...], {...}, `...`

Tuple, list,[c] dictionary, conversion to string[d]

[a] Comparison operators may be chained: x < y < z is similar to x < y and y < z, except that y is evaluated only once in the first format.

[b] Floor division (X // Y), new in 2.2, always truncates fractional remainders. Classic division (X / Y) truncates integer division results in 2.2 but will ...

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