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package body Relop_Example_Token is
---------------------------------------------------------------------------
-- This procedure will be called when analysis on a new candidate string
-- is started. The Token needs to clear its state (if any).
---------------------------------------------------------------------------
overriding procedure Clear (The_Token : in out Instance) is
begin
The_Token.State := First_Char;
end Clear;
---------------------------------------------------------------------------
-- This procedure will be called to create a Relop token recognizer
---------------------------------------------------------------------------
function Get return Instance is
begin
return (Report => True,
State => First_Char);
end Get;
--------------------------------------------------------------------------
-- This procedure will be called to perform further analysis on a token
-- based on the given next character.
---------------------------------------------------------------------------
overriding procedure Analyze
(The_Token : in out Instance;
Next_Char : in Character;
Verdict : out OpenToken.Recognizer.Analysis_Verdict)
is begin
case The_Token.State is
when First_Char =>
-- If the first char is a <, =, or >, its a match
case Next_Char is
when '<' =>
Verdict := OpenToken.Recognizer.Matches;
The_Token.State := Equal_or_Greater;
when '>' =>
Verdict := OpenToken.Recognizer.Matches;
The_Token.State := Equal;
when '=' =>
Verdict := OpenToken.Recognizer.Matches;
The_Token.State := Done;
when others =>
Verdict := OpenToken.Recognizer.Failed;
The_Token.State := Done;
end case;
when Equal_or_Greater =>
-- If the next char is a > or =, its a match
case Next_Char is
when '>' | '=' =>
Verdict := OpenToken.Recognizer.Matches;
The_Token.State := Done;
when others =>
Verdict := OpenToken.Recognizer.Failed;
The_Token.State := Done;
end case;
when Equal =>
-- If the next char is a =, its a match
if Next_Char = '=' then
Verdict := OpenToken.Recognizer.Matches;
The_Token.State := Done;
else
Verdict := OpenToken.Recognizer.Failed;
The_Token.State := Done;
end if;
when Done =>
Verdict := OpenToken.Recognizer.Failed;
end case;
end Analyze;
end Relop_Example_Token;
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