**********************************pos:****************************************
Returns the index value of the first character in a specified substring that occurs in a given string.
Unit
System
Category
string handling routines
Delphi syntax:
function Pos(Substr: string; S: string): Integer;
Description
In Delphi, Pos searches for a substring, Substr, in a string, S. Substr and S are string-type expressions.
Pos searches for Substr within S and returns an integer value that is the index of the first character of Substr within S. Pos is case-sensitive. If Substr is not found, Pos returns zero.
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