Parts of the expression contained within parentheses are called tokens.
The regular expression for the ParseErrorMessage property is as follows:
([^(]+)[(]([0-9]+)[)] [:] (error|warning|fatal error)
It consists of the following parts:
The ErrorMessageTokensFormat property works with ParseErrorMessage to determine how many tokens can be contained in an error message, and the relative positions in the message string of tokens that represent the file name and line number of the error. The second token in the sample regular expression would most likely represent a line number, depending on how ErrorMessageTokensFormat was defined.
Based on this regular expression, the parser would interpret the string "(3457):warning" as a valid error message indicating a warning condition at line 3457 in the program.