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{–}

program Types;

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{ Constant Declarations }

const TAB = ^I;

CR = ^M;

LF = ^J;

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{ Variable Declarations }

var Look: char; { Lookahead Character }

ST: Array['A'..'Z'] of char;

{–}

{ Read New Character From Input Stream }

procedure GetChar;

begin

Read(Look);

end;

{–}

{ Report an Error }

procedure Error(s: string);

begin

WriteLn;

WriteLn(^G, 'Error: ', s, '.');

end;

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{ Report Error and Halt }

procedure Abort(s: string);

begin

Error(s);

Halt;

end;

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{ Report What Was Expected }

procedure Expected(s: string);

begin

Abort(s + ' Expected');

end;

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{ Dump the Symbol Table }

procedure DumpTable;

var i: char;

begin

for i := 'A' to 'Z' do

WriteLn(i, ' ', ST[i]);

end;

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{ Recognize an Alpha Character }

function IsAlpha(c: char): boolean;

begin

IsAlpha := UpCase(c) in ['A'..'Z'];

end;

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{ Recognize a Decimal Digit }

function IsDigit(c: char): boolean;

begin

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

end;

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{ Recognize an AlphaNumeric Character }

function IsAlNum(c: char): boolean;

begin

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

end;

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{ Recognize an Addop }

function IsAddop(c: char): boolean;

begin

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

end;

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{ Recognize a Mulop }

function IsMulop(c: char): boolean;

begin

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

end;

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{ Recognize a Boolean Orop }

function IsOrop(c: char): boolean;

begin

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

end;

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{ Recognize a Relop }

function IsRelop(c: char): boolean;

begin

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

end;

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{ Recognize White Space }

function IsWhite(c: char): boolean;

begin

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

end;

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{ 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;

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{ Match a Specific Input Character }

procedure Match(x: char);

begin

if Look = x then GetChar

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

SkipWhite;

end;

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{ Get an Identifier }

function GetName: char;

begin

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

GetName := UpCase(Look);

GetChar;

SkipWhite;

end;

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{ Get a Number }

function GetNum: char;

begin

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

GetNum := Look;

GetChar;

SkipWhite;

end;

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{ Output a String with Tab }

procedure Emit(s: string);

begin

Write(TAB, s);

end;

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{ Output a String with Tab and CRLF }

procedure EmitLn(s: string);

begin

Emit(s);

WriteLn;

end;

{–}

{ Initialize }

procedure Init;

var i: char;

begin

for i := 'A' to 'Z' do

ST[i] := '?';

GetChar;

SkipWhite;

end;

{–}

{ Main Program }

begin

Init;

DumpTable;

end.

{–}