enumerated-type
Small utility library implementing enum types that can be used in switch statements, can have an optional property used as the key for the enum values, have shared properties for all values and each enum value can have own properties.
Install
Use npm to install.
npm install enumerated-type --save
Usage
Use new Enum(enumName, keyPropName, values, commonProperties)
to define an enum for given
values. The property values of the values
object can be objects/arrays/functions or
non-objects.
Defining an enum using objects as values:
// NOTE: defining the enum using intermediate objects allows JetBrains IDEs completion to work better with enums and enum values
// common enum value properties, instance enum values can override these with their own definitions
const StepTypeValue = {
stepTypeId: 0,
isDuty: false,
isVariable: false,
isOptional: false,
isGateway: false,
isXor: false,
isAnd: false,
isCombined: false,
};
// NOTE: defining the enum using intermediate objects allows JetBrains IDEs completion to work better with enums and enum values
// enum value properties
let StepType = {
duty: { stepTypeId: 1, isDuty: true, },
variable: { stepTypeId: 2, isVariable: true, },
optional: { stepTypeId: 3, isOptional: true, },
xor: { stepTypeId: 4, isGateway: true, isXor: true, },
and: { stepTypeId: 5, isGateway: true, isAnd: true, },
combineXor: { stepTypeId: 6, isGateway: true, isXor: true, isCombined: true, },
combineAnd: { stepTypeId: 7, isGateway: true, isAnd: true, isCombined: true, },
stepTypeId(value) {
return StepTypeValue;
},
};
StepType = new Enum("StepType", StepType, StepTypeValue, "stepTypeId");
commonProperties
are used for each enum value for its prototype, therefore they provide a
default value when the enum value does not define the property directly:
const values = [];
for (let value of StepType) {
values.push({
isAnd: value.isAnd,
isCombined: value.isCombined,
isDuty: value.isDuty,
isGateway: value.isGateway,
isOptional: value.isOptional,
isVariable: value.isVariable,
isXor: value.isXor,
name: value.name,
stepTypeId: value.stepTypeId,
});
}
expect(values).toEqual([
{ "isAnd": false, "isCombined": false, "isDuty": true, "isGateway": false, "isOptional": false, "isVariable": false, "isXor": false, "name": "duty", "stepTypeId": 1, },
{ "isAnd": false, "isCombined": false, "isDuty": false, "isGateway": false, "isOptional": false, "isVariable": true, "isXor": false, "name": "variable", "stepTypeId": 2, },
{ "isAnd": false, "isCombined": false, "isDuty": false, "isGateway": false, "isOptional": true, "isVariable": false, "isXor": false, "name": "optional", "stepTypeId": 3, },
{ "isAnd": false, "isCombined": false, "isDuty": false, "isGateway": true, "isOptional": false, "isVariable": false, "isXor": true, "name": "xor", "stepTypeId": 4, },
{ "isAnd": true, "isCombined": false, "isDuty": false, "isGateway": true, "isOptional": false, "isVariable": false, "isXor": false, "name": "and", "stepTypeId": 5, },
{ "isAnd": false, "isCombined": true, "isDuty": false, "isGateway": true, "isOptional": false, "isVariable": false, "isXor": true, "name": "combineXor", "stepTypeId": 6, },
{ "isAnd": true, "isCombined": true, "isDuty": false, "isGateway": true, "isOptional": false, "isVariable": false, "isXor": false, "name": "combineAnd", "stepTypeId": 7, },
]);
Use enum values as property names:
let obj = {};
obj['duty'] = "++duty";
obj[StepType.duty] = "--duty";
obj[StepType.variable] = "--variable";
obj[StepType.optional] = "--optional";
obj[StepType.xor] = "--xor";
obj[StepType.and] = "--and";
obj[StepType.combineXor] = "--combineXor";
obj[StepType.combineAnd] = "--combineAnd";
expect(obj.duty).toEqual('++duty');
let values = [];
StepType.forEach(value => {
values.push(obj[value]);
});
expect(values).toEqual([
"--duty",
"--variable",
"--optional",
"--xor",
"--and",
"--combineXor",
"--combineAnd",
]);
Enum Instance Properties
.name
: name of the enum passed to constructor.values
: array of enum values sorted bykeyPropName
if provided or byvalue
if non-object values..keys
: array of enum key properties if keyPropName was passed to constructor, otherwise array of enum values which were not objects[keyPropName](key)
: function taking key and returning enum value whosekeyPropName
equals the value of the key. Only defined ifkeyPropName
is defined and is a string. Convenience method for converting key property value to an enum value..value(key)
: function taking the a value and returning enum value whose value equals the key. Only defined ifkeyPropName
is not defined..filter
:function (callback, thisArg)
taking a callbackfunction(value, index, values)
and returning array of values for which callback result tested true, unless callback returnsBREAK(result)
orRETURN(result)
. see for-each-break.forEach
:function (callback, thisArg, defaultResult)
taking a callbackfunction(value, index, values)
and optional default result if callback does not returnBREAK(result)
orRETURN(result)
. see for-each-break.map
:function (callback, thisArg)
taking a callbackfunction(value, index, values)
and returning array of values returned my callback, unless callback returnsBREAK(result)
orRETURN(result)
. see for-each-break.filterRight
:function (callback, thisArg, thisArg)
taking a callbackfunction(value, index, values)
and returning array of values for which callback result tested true, unless callback returnsBREAK(result)
orRETURN(result)
. see for-each-break.forEachRight
:function (callback, thisArg, thisArg, defaultResult)
taking a callbackfunction(value, index, values)
and optional default result if callback does not returnBREAK(result)
orRETURN(result)
. see for-each-break.mapRight
:function (callback, thisArg, thisArg)
taking a callbackfunction(value, index, values)
and returning array of values returned my callback, unless callback returnsBREAK(result)
orRETURN(result)
. see for-each-break[Symbol.iterator]
: iterator over enum values[Symbol.hasInstance]
: handlesinstanceof
and returns true when left hand side is an enum value of this enum instance..toString
: returns[object Enum(enumName)]
Enum Value Instance Properties
In addition to enum value properties passed for the value each enum value has the following additional properties:
.enum
: parent enum instance..name
: name of the enum value (property name in values object passed toEnum()
constructor..value
: Symbol(name) symbol instance for the property name of the enum value..index
: the enum value's index within enum instances values array..next
: enum value after this enum orundefined
if last enum value..previous
: enum value before this enum orundefined
if first enum value.[Symbol.toPrimitive]
: returnsvalue
property forstring
ordefault
hint, fornumber
returns the enum value's index within enum instances values array.
commonProperties
will
have this
set to the enum value instance.
License
MIT, see LICENSE.md for details.