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Val procedure
Converts a string to a numeric representation.
Unit
System
Category
string handling routines
procedure Val(S
var V
var Code: Integer);
Description
Val converts the string value S to its numeric representation,
as if it were read from a text file with Read.
S is a string-type expression
it must be a sequence of characters
that form a signed real number.
V is an integer-type or real-type variable. If V is an integer-type variable,
S must form a whole number.
Code is a variable of type Integer.
If the string is invalid, the index of the offending character is stored
in Code
otherwise, Code is set to zero. For a null-terminated string,
the error position returned in Code is one larger than the actual
zero-based index of the character in error.
Val performs range checking differently depending upon the setting
of the $R compiler directive and the type of the parameter V.
Setting Result
{$R+} An out-of-range value always generates a run-time error.
{$R-} The values for out-of-range vary depending upon the data type of V.
