Substring index of string

As of version 8 of TEM, you can retrieve indexed substring values:

Q: substring(0, 3) of "abcdefgh"
A: abc

This expression returns the first three characters of the specified string. The starting value is zero-based, so to find a substring starting at the fourth character, use and expression like this:

Q: substring(3, 3) of "abcdefgh"
A: def

You can concatenate the substrings you find as well. For instance, to produce a series of hex bytes from a string of hex characters, use an expression like the following:

Q: concatenation "," of substrings (integers in (0, length of it, 2), 2) of 
"00000b00010002000000000000000000"
A: 00,00,0b,00,01,00,02,00,00,00,00,00,00,00,00,00

This expression uses the integers in command, that returns a list of number pairs with a starting number (starting at 0) and a step size (2):

Q: (integers in (0, length of it, 2), 2) of "123456"
A: 0, 2
A: 2, 2
A: 4, 2
A: 6, 2

Since we want two-digit hex values here, we add the ",2" to the starting values.