This disclosure relates generally to a tool, system, and method for searching input data. The system may include a pattern input module, configured to receive regular expression patterns of symbols. An interpreter module may be configured to access individual ones of the symbols of the input data and upon accessing each symbol and compare a thread against the symbol. For each pattern, the thread corresponding to the pattern is compared against the symbol prior to the at least one thread being compared against a subsequent symbol of the input data. An output module may be configured to output an indication of ones of the patterns determined to be contained within the input data based on the comparison of the corresponding at least one thread to the symbols of the input data.