vault backup: 2025-08-08 22:44:15HEADmain

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+[[Pointer safety principle]]
+[[Variables are subject to permissions similar to files on linux]]
+[[Lifetime specifier]]
+[[When heap data is deallocated]]
+[[Variables lives on the stack]]
+[[Ownership]]
+
+This is literally talking about heap data and references (ie `&String`): the heap data must not be freed when we try to use a reference to it.
+
+This is enforced in one of two ways.
+
+Firstly, if a reference is created to a variable it loses its Own permission: thus we can't drop it, because the compiler expects that permission on the place where it is dropped.
+
+Secondly, it uses the Flow permission and requires a a lifetime specifier when we return things from functions.
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