After reading the resources that you all posted, and re-reading my chapter, I have mangaed to narrow my question. Obviously, the way that I am reading this code is incorrect because I don't think that it should work but when I tested it I found that it did. Please tell me where my error in thinking is. It comes straight from my perl book. It is supposed to parse a string in order to determine if the string contains aeiou in order. 
#!/usr/bin/perl -w
while (<>) {
print if
(/^[^aeiou]*a[^eiou]*e[^aiou]*i[^aeou]*o[^aeiu]*u[^aeio]*$/);
}

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It is my understanding that the code should match if and only if there is a non vowel character at the beginning of the string, an a followed by any number of characters except for other vowels, an e followed by any number of characters except for any number of vowels etc... and finally a u followed by any number of characters that are not other vowels at the end of the string. My questions: -The ^ anchor before the first set of brackets seems to me to say that the string must begin with a non vowel character in order to match. I tested this theory and as long as the vowels are in order the string can begin with a non vowel character. How does that work? -Why does the if statement not require brackets? -Why is the $ anchor necessary at the end? Wouldn't the regular expression do the same thing if it were left off? Thanks!!!

In reply to Re^3: Regular Expression by Socrates440
in thread Regular Expression by Socrates440

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