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vim option: compatible

When this option is set, it empties indentexpr
In the source code, the value of the compatible option is stored in c_cp which is (externally) declared in option.h.
Executing :set compatible or :set nocompatible eventually calls compatible_set().

Differences between compatible and nocompatible

To be finished…!
compatible nocompatible
Filename completion (:e …) ctrl-e tab

Overwritting other options

Setting nocompatible overwrites at the viminfo option, therefore, set nocompatible should be placed at the beginning of the vimrc file, see this stackoverflow answer.
Other options that set nocompatible also overwrites include

See also

Because set nocompatible overwrites other options, it should be placed at the beginning of the vimrc file.
vim options

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