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31 lines
915 B
Markdown
31 lines
915 B
Markdown
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# Arithmetic evaluation (command)
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## Synopsis
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(( <EXPRESSION> ))
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## Description
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This command evaluates the [arithmetic expression](/syntax/arith_expr)
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`<EXPRESSION>`.
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If the expression evaluates to 0 then the exit code of the expression is
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set to 1 (`FALSE`). If the expression evaluates to something else than
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0, then the exit code of the expression is set to 0 (`TRUE`). For this
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return code mapping, please see [this
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section](/syntax/arith_expr#arithmetic_expressions_and_return_codes).
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The functionality basically is equivalent to what the [`let` builtin
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command](/commands/builtin/let) does. The arithmetic evaluation compound
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command should be preferred.
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## Examples
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## Portability considerations
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## See also
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- Internal: [arithmetic expressions](/syntax/arith_expr)
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- Internal: [arithmetic expansion](/syntax/expansion/arith)
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- Internal: [The `let` builtin command](/commands/builtin/let)
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