616640a128
The mallet operator is similar to the current memoization operator, except it can be used outside of just objects. In Ruby, it’s almost the same as `a = a || b`. Note that only `nil` and `false` are falsey in Ruby. I’ve defined it as `== null`, though that could be changed to any JS falsey value.
57 lines
797 B
JavaScript
57 lines
797 B
JavaScript
var obj = {};
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obj.x ||= 2;
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assert.equal(obj.x, 2);
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obj = {};
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assert.equal(obj.x ||= 2, 2);
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obj = { x: 1 };
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obj.x ||= 2;
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assert.equal(obj.x, 1);
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obj = { x: 1 };
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assert.equal(obj.x ||= 2, 1);
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obj = { x: undefined }
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obj.x ||= 2;
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assert.equal(obj.x, 2);
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obj = { x: undefined }
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assert.equal(obj.x ||= 2, 2);
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obj = { x: null }
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obj.x ||= 2;
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assert.equal(obj.x, 2);
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obj = { x: null }
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assert.equal(obj.x ||= 2, 2);
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obj = { x: false }
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obj.x ||= 2;
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assert.equal(obj.x, false);
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obj = { x: false }
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assert.equal(obj.x ||= 2, false);
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obj = undefined;
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obj ||= 2;
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assert.equal(obj, 2);
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obj = undefined;
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assert.equal(obj ||= 2 , 2);
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obj = 1;
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obj ||= 2;
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assert.equal(obj, 1);
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obj = 1;
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assert.equal(obj ||= 2 , 1);
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obj = null;
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obj ||= 2;
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assert.equal(obj, 2);
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obj = null;
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assert.equal(obj ||= 2 , 2);
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