Ruby String Scanner

Given the string test string here are the pertinent scan pointer positions.

Ruby string scanner.

Ruby regular expressions ruby regex for short help you find specific patterns inside strings with the intent of extracting data for further processing two common use cases for regular expressions include validation parsing. Advancing the scan pointer. Advances the scan pointer if advance pointer p otherwise not. This method does affect the match register.

This method does affect the match register. In other words your program will be able to tell. You can access the most recent match. The point of scanning is to move forward a bit at a time so matches are sought after the scan pointer.

Scan is a stringscanner class method which tries to match with pattern at the current position. Think about an email address with a ruby regex you can define what a valid email address looks like. Scans the string until the pattern is matched. Advances the scan pointer if advance pointer p otherwise not.

Scans the string until the pattern is matched. You can look ahead in the string without actually scanning. Scanning a string means remembering the position of a scan pointer which is just an index. Returns the matched string if return string p is true otherwise returns the number of bytes advanced.

There are other methods besides the plain scanners.