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'9'];

end;

{–}

{ Recognize an AlphaNumeric Character }

function IsAlNum(c: char): boolean;

begin

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

end;

{–}

{ Recognize an Addop }

function IsAddop(c: char): boolean;

begin

IsAddop := c in ['+', '-'];

end;

{–}

{ Recognize a Mulop }

function IsMulop(c: char): boolean;

begin

IsMulop := c in ['*', '/'];

end;

{–}

{ Recognize a Boolean Orop }

function IsOrop(c: char): boolean;

begin

IsOrop := c in ['|', '~'];

end;

{–}

{ Recognize a Relop }

function IsRelop(c: char): boolean;

begin

IsRelop := c in ['=', '#', '<', '>'];

end;

{–}

{ Recognize White Space }

function IsWhite(c: char): boolean;

begin

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

end;

{–}

{ Skip Over Leading White Space }

procedure SkipWhite;

begin

while IsWhite(Look) do

GetChar;

end;

{–}

{ Skip Over an End-of-Line }

procedure Fin;

begin

if Look = CR then begin

GetChar;

if Look = LF then

GetChar;

end;

end;

{–}

{ Match a Specific Input Character }

procedure Match(x: char);

begin

if Look = x then GetChar

else Expected('''' + x + '''');

SkipWhite;

end;

{–}

{ Get an Identifier }

function GetName: char;

begin

if not IsAlpha(Look) then Expected('Name');

GetName := UpCase(Look);

GetChar;

SkipWhite;

end;

{–}

{ Get a Number }

function GetNum: char;

begin

if not IsDigit(Look) then Expected('Integer');

GetNum := Look;

GetChar;

SkipWhite;

end;

{–}

{ Output a String with Tab }

procedure Emit(s: string);

begin

Write(TAB, s);

end;

{–}

{ Output a String with Tab and CRLF }

procedure EmitLn(s: string);

begin

Emit(s);

WriteLn;

end;

{–}

{ Post a Label To Output }

procedure PostLabel(L: string);

begin

WriteLn(L, ':');

end;

{–}

{ Load a Variable to the Primary Register }

procedure LoadVar(Name: char);

begin

CheckVar(Name);

EmitL

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