John Carmack on Mutable Variables

Re:John Carmack on Mutable Variables by kubanczyk on Saturday November 01, 2025 @01:27PM (#45783489)

Taking your point of view: you assigned a value1 to a name. Then you assigned a value2 to the same name.

You say that value2 is correct. It logically follows that value1 was incorrect. Why did you assign it then?

The names are free, you can just use a correct name every single time.

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Re:John Carmack on Mutable Variables by zaphirplane on Sunday November 02, 2025 @07:08AM (#45789722)

Because the account owner withdrew money . The player scored a goal, the month ticked over, the rain started, the car accelerated, a new comment was added to the thread .

The world by definition mutates over time.

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Re:John Carmack on Mutable Variables by kubanczyk on Sunday November 02, 2025 @09:38AM (#45790636)

Ah, true. If the var is a part of a long-living state, all good. That's just rarely seen in CRUD apps, more common in games.

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