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VIM struct: regprog_T

An instance of regprog_T is returned by vim_regcomp(). It needs to be passed to vim_regexec().
This is a «base» struct, the two specific (derived, sort of) structs are regmatch_T (used for single-line matching) and regmmatch_T (used for multi-line matching). 
typedef struct regprog
{
    regengine_T        *engine;
    unsigned            regflags;
    unsigned            re_engine;   // automatic, backtracking or nfa engine
    unsigned            re_flags;    // second argument for vim_regcomp()
    int                 re_in_use;   // prog is being executed
} regprog_T;

See also

A regprog_T* is used for a compiled regexp program in the AutoPat struct.

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