JavaScript idiom for limiting a string to a number of discrete values
In C# I might use an enumeration.
In JavaScript, how can I limit a value to a set of discrete values idiomatically?
We sometimes define a variable in a JS class 'Enumerations' along these lines:
var Sex = {
Male: 1,
Female: 2
};
And then reference it just like a C# enumeration.
There is no enumeration type in JavaScript. You could, however, wrap an object with a getter and setter method around it like
var value = (function() {
var val;
return {
'setVal': function( v ) {
if ( v in [ listOfEnums ] ) {
val = v;
} else {
throw 'value is not in enumeration';
}
},
'getVal': function() { return val; }
};
})();
Basically, you can't.
Strong typing doesn't exist in JavaScript, so it's not possible to confine your input parameters to a specific type or set of values.
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