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Instant-use add-on functions for the Wolfram Language
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Scoped let expression with pattern variables
ResourceFunction["LetScope"][set,expr] binds pattern variables in set to substitute in expr. | |
ResourceFunction["LetScope"][set1,set2,…,expr] uses multiple nested set patterns. |

Pattern match and use the pattern variable:
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Use any pattern:
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Nest multiple patterns:
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Use LeftArrow (←) as an alternative symbol for let bindings:
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Unmatched variables bind to Sequence[]:
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Pattern variables inside Verbatim are ignored:
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Unevaluated can be used to delay evaluation:
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Variable names can be reused:
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Use intermediate non-binding expressions to evaluate in between:
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Because LetScope is HoldAllComplete, Sequence can be returned:
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Use LetScope as a scope with support for binding to multiple variables:
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Use LetScope for destructuring any expression with pattern matching:
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Compound nested scope with dependencies:
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For a single binding LetScope is equivalent to a substitution with Replace:
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For a single variable left-hand-side LetScope is similar to ResourceFunction["CompoundScope"]:
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LetScope effectively applies binding rules (similar to ResourceFunction["PatternBindings"]) to consequent expressions:
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Wolfram Language 14.0 (January 2024) or above
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