state = start
    input->remember-starting-position
    
    while (input->has-more) {
        state = state->transition-for (input->current-char)
            || error-state                              # move
        
        if (state->is-error) {
            push (output-queue, token {                 # token
                type = last-accept-state->type
                value = input->last-accepted-string
            })
            input->rewind                               # rewind
            state = start                               # restart
            input->remember-starting-position
        } else {
            if (state->accepts) {                       # memo
                last-accept-state = state
                input->remember-accept-position
            }
            input->advance                              # advance
        }
    }