Оптимальні програми

IsDigit := c In ['0'..'9'];

End;

Function IsAlNum(c: Char): Boolean;

Begin

IsAlNum := IsAlpha(c) Or IsDigit(c);

End;

Function IsAdDop(c: Char): Boolean;

Begin

IsAdDop := c In ['+', '-'];

End;

Function IsWhite(c: Char): Boolean;

Begin

IsWhite := c In [' ', TAB];

End;

Procedure SkipWhite;

Begin

While IsWhite(Look) Do

GetChar;

End;

Procedure Match(x: Char);

Begin

If Look <> x Then Expected('''' + x + '''')

Else Begin

GetChar;

SkipWhite;