when writing switch-like logic, python
switch = {
"a":print(1),
"b":print(2),
"c":print(3)
}
try:
switch["c"]
except KeyError as e:
passthis is 1 2 3 instead of the expected 3. Ask what is the reason for this
when writing switch-like logic, python
switch = {
"a":print(1),
"b":print(2),
"c":print(3)
}
try:
switch["c"]
except KeyError as e:
passthis is 1 2 3 instead of the expected 3. Ask what is the reason for this
do not use print in dict.
The print function executes before it is assigned to switch, so 1 / 2 / 3 is printed, when in fact, switch is {"a": None, "b": None, "c": None} , because the return value of print is None.
you can write:
switch = {"a": 1, "b": 2, "c": 3}
try:
print(switch["c"])
except KeyError as e:
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