I find in some place following sentence:
- Mike, as a seargent of the police I came to the office
at 9. Always.
- OK boss. But once I have come at 9 and there was no one over here.
Is it right to use perfect form here? The "once" is suspicious.
But, in speech, this strong tendency is sometimes overcome by semantic considerations. Also there is a reason for a speaker to use this adverb, 'once' with the present perfect, the present perfect of experience;
Have you ever come here at 9 AM? How many times have you come here at 9 AM?
I think it would have sounded more "natural" if it had been phrased,CGEL (at page 144)
This use of the present perfect [experential] allows for the inclusion, under restrictive conditions, of a past time adjunct.
- OK boss. But I have come here once at 9 and there was no one over here.
Remember, the strong tendency that native spekaers have to follow certain "rules" can be overridden for other important language considerations.
Thank you, it is clear now.
Just for training : Can I use the past perfect in the same context , like
"- OK boss. But yesterday I had come by 9 and there was no one over here."