substriings



What is the function which pulls substrings out of a string, or, 
, e.g., writes out the characters in a string as a list.

Also, if this is easy to find in the manual, please tell me where.


For instance, which function 'f' will do the following.

(%i1) f("world");

(%o1) orl

or just the following.

(%i2) f("world");

(%o1) w

That is, extract the first letter of the string.

TIA,
  -sen


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