2017-04-27 20:33:15 +01:00
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# see https://docs.python.org/3/reference/expressions.html#operator-precedence
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# '|' is the least binding numeric operator
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# '^'
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# OK: 1 | (2 ^ 3) = 1 | 1 = 1
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# BAD: (1 | 2) ^ 3 = 3 ^ 3 = 0
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print(1 | 2 ^ 3)
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# '&'
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# OK: 3 ^ (2 & 1) = 3 ^ 0 = 3
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# BAD: (3 ^ 2) & 1 = 1 & 1 = 1
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print(3 ^ 2 & 1)
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# '<<', '>>'
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# OK: 2 & (3 << 1) = 2 & 6 = 2
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# BAD: (2 & 3) << 1 = 2 << 1 = 4
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print(2 & 3 << 1)
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# OK: 6 & (4 >> 1) = 6 & 2 = 2
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# BAD: (6 & 4) >> 1 = 2 >> 1 = 1
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print(6 & 4 >> 1)
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# '+', '-'
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# OK: 1 << (1 + 1) = 1 << 2 = 4
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# BAD: (1 << 1) + 1 = 2 + 1 = 3
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print(1 << 1 + 1)
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# '*', '/', '//', '%'
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# OK: 2 + (2 * 2) = 2 + 4 = 6
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# BAD: (2 + 2) * 2 = 4 * 2 = 8
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print(2 + 2 * 2)
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# '+x', '-x', '~x'
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# '**'
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# OK: -(2**2) = -4
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# BAD: (-2)**2 = 4
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print(-2**2)
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# OK: 2**(-1) = 0.5
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2018-07-22 15:19:22 +01:00
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print(2**-0)
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2017-04-27 20:33:15 +01:00
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# (expr...)
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print((2 + 2) * 2)
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