static bool IsPalindrome(string str)
{
int len;
len = StringLength(str);
if (len <= 1) {
return (TRUE);
} else {
return (IthChar(str, 0) == IthChar(str, len - 1)
&& IsPalindrome(SubString(str, 1, len - 2)));
}
}
static bool IsLegalWord(string token)
{
int i;
for (i = 0; i < StringLength(token); i++) {
if (!isalpha(IthChar(token, i))) return (FALSE);
}
return (TRUE);
}
static int FindFirstVowel(string word)
{
int i;
for (i = 0; i < StringLength(word); i++) {
if (IsVowel(IthChar(word, i))) return (i);
}
return (-1);
}
static void skipWhitespaceCharacters(void)
{
if(skipWhitespace) /* Do we have to skip? */
{
/* Skip characters as long as whitespace is found: */
while(cpos < buflen && isspace(IthChar(buffer, cpos)))
++cpos;
}
}
string GetNextToken(void)
{
char ch;
int start;
string result;
/* Check for error condition: */
if(cpos >= buflen)
Error("No more tokens");
/* Depending on the package mode, we have to skip
whitespace characters: */
skipWhitespaceCharacters();
/* Retrieve the next character: */
ch = IthChar(buffer, cpos);
/* Based on that character, either scan a string or return the character: */
if(isalnum(ch)) /* Character is alphanumeric: */
{
/* Remember the start of the string: */
start = cpos;
/* Iterate until a non-alphanumeric character is encountered: */
while(cpos < buflen && isalnum(IthChar(buffer, cpos)))
++cpos;
/* Return the substring from start to the current character position: */
result = SubString(buffer, start, cpos - 1);
}
else /* Character is not alphanumeric: */
{
++cpos;
result = CharToString(ch);
}
/* Depending on the package mode, we have to skip
whitespace characters again: */
skipWhitespaceCharacters();
return result;
}
