hashPointer

pub fn hashPointer(hasher: anytype, key: anytype, comptime strat: HashStrategy) void {
    const info = @typeInfo(@TypeOf(key));

    switch (info.pointer.size) {
        .one => switch (strat) {
            .Shallow => hash(hasher, @intFromPtr(key), .Shallow),
            .Deep => hash(hasher, key.*, .Shallow),
            .DeepRecursive => hash(hasher, key.*, .DeepRecursive),
        },

        .slice => {
            switch (strat) {
                .Shallow => {
                    hashPointer(hasher, key.ptr, .Shallow);
                },
                .Deep => hashArray(hasher, key, .Shallow),
                .DeepRecursive => hashArray(hasher, key, .DeepRecursive),
            }
            hash(hasher, key.len, .Shallow);
        },

        .many,
        .c,
        => switch (strat) {
            .Shallow => hash(hasher, @intFromPtr(key), .Shallow),
            else => @compileError(
                \\ unknown-length pointers and C pointers cannot be hashed deeply.
                \\ Consider providing your own hash function.
            ),
        },
    }
}