(1) See Expression Studio.
(2) In programming, a line of source code that returns a value when executed. An expression can comprise any combination of variables, values, operators and functions. For example, a=b+c and price=2*cost are expressions. The more complicated expression (strlen(text_string)*2) is a C example that uses a string length function and returns a value that is twice the number of characters in the string of text. See regular expression.
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