Count

This function takes a string parameter and returns a natural number representing the number of characters of the incoming string.

Concatenation

This function takes two string parameters A and B and returns a string that represents B appended to the end of A.

Substring

This function takes a string parameter A and two numeric parameters, X and Y, and returns a sub-string of A that comprises from the character at the index X to that at Y, given that strings' total range spans from 0 to n-1, where n is the number of characters of the string.

Index of

This function takes two string operands, A and B, and returns an integer with the index in A where the first occurrence of B starts. If B does not occur in a, it returns -1.

To upper case

This function takes a string and returns a string which contains the same characters in the same order where lower case letters have been replaced by capital letters.

To lower case

This function takes a string and returns a string which contains the same characters in the same order where capital letters have been replaced by lower case letters.

First upper

This function takes a string and returns a representation of the same string where the letter at the index 0 has been capitalized.

Contains

This function takes two input strings A and B. It returns true only if first string A contains the whole string B.

Match regular expression

This function takes a string A and a string representing a standard regular expression R and returns true if A matches the expression R, and false otherwise.

If you need more information about regular expressions and how they can be created, please refer to http://en.wikipedia.org/wiki/Regular_expression. However, you won't always need to build your own regular expressions, for the Justinmind Prototyper provides some of the most useful constructions ready-to-use. Refer to the Regular expression constants