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Is there a way to see if a string can be extended with a few characters to match some given regular expression? Can I do it using Regex class? I’ve googled it for a while and it seems like I should write my own regex parser…
Like Alex said: If the pattern is abc the string ab would match my criteria and the string def or bc wouldn’t. And I want this to work for any regular expression which is unknown at compile time.
Regular expressions are compiled into decision trees that allow for deciding a match for input of length n in O(n) time. Your custom RE parser could simply count the number of decisions until failure, which when compared with the number of steps necessary for a match, would indicate the “closeness” of the argument to the RE. Assuming you’re using fairly simple RE’s, and by “extended” mean adding characters to the end of the string, this would be computationally feasible.