Can anyone explain why the veritcal bar symbol ("|") is matching with every string pattern. What is the solution for the issue.
> grepl("|", "DateNumber")
[1] TRUE
> grepl("|", "Dat")
[1] TRUE
> grepl("|", "t")
[1] TRUE
> grepl("|", "")
[1] TRUE
> grep("|", "Date Number")
[1] 1
> grep("|", "DateNumber")
[1] 1
> grep("|", "Date")
[1] 1
Thanks in Advance.