xor
x xor y
xor(x, y)
Logical exclusive or, xor. Test whether one and only one value is defined with a nonzero/nonempty value.
Try it yourself:
| $1 | true xor false
| |
| $2 | false xor false
| |
| $3 | true xor true
| |
| $4 | 0 xor 4
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