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In programming, a function can have optional parameters, for instance getTemperature() could have an optional parameter "Unit" to say I want the temperature in Kelvin for instance. By default, when specifying no parameter, it would be in Celsius.

How to say optional parameters in Japanese?

ALC says オプションのパラメータ:

Both required and optional parameters are listed.

But I believe they are wrong, and their translation has a different meaning.

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up vote 3 down vote accepted

You are looking for

必須(の/な)引数 => required parameter(s).


任意(の/な)引数 => optional parameter(s)

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