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5.6 Block Statements

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A block_statement encloses a handled_sequence_of_statements optionally preceded by a declarative_part.

Syntax

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block_statement::=
   [block_statement_identifier:]
       [declare
            declarative_part]
        begin
            handled_sequence_of_statements
        end [block_identifier];

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If a block_statement has a block_statement_identifier, then the identifier shall be repeated after the end; otherwise, there shall not be an identifier after the end.
Static Semantics

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A block_statement that has no explicit declarative_part has an implicit empty declarative_part.

Dynamic Semantics

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The execution of a block_statement consists of the elaboration of its declarative_part followed by the execution of its handled_sequence_of_statements.

Examples

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Example of a block statement with a local variable:

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     Swap:
        declare
           Temp Integer;
        begin
           Temp := V; := U; := Temp;
        end Swap;