16 lines
445 B
Markdown
16 lines
445 B
Markdown
# Default Expression
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A `default` expression specifies a fallback selected during materialization when no explicit value exists.
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```dcdl
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port = Int default 8080;
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```
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`default` is not a constraint.
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See [Constraints and Defaults](../constraints-and-defaults.md) for details.
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## Evaluation
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The fallback expression is evaluated only if materialization requires it.
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When an explicit value exists, the `default` is neither evaluated nor selected.
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