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procedure Block;

begin

Scan;

while not(Token in ['e', 'l']) do begin

case Token of

'i': DoIf;

'w': DoWhile;

'R': DoRead;

'W': DoWrite;

else Assignment;

end;

Scan;

end;

end;

{–}

{ Allocate Storage for a Variable }

procedure Alloc;

begin

Next;

if Token <> 'x' then Expected('Variable Name');

CheckDup(Value);

AddEntry(Value, 'v');

Allocate(Value, '0');

Next;

end;

{–}

{ Parse and Translate Global Declarations }

procedure TopDecls;

begin

Scan;

while Token = 'v' do

Alloc;

while Token = ',' do

Alloc;

end;

{–}

{ Initialize }

procedure Init;

begin

GetChar;

Next;

end;

{–}

{ Main Program }

begin

Init;

MatchString('PROGRAM');

Header;

TopDecls;

MatchString('BEGIN');

Prolog;

Block;

MatchString('END');

Epilog;

end.

{–}