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Instant-use add-on functions for the Wolfram Language
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A version of Import which uses a cache of the result unless the source file has changed
ResourceFunction["ImportOnce"][file,opts] imports data from file, caching the result unless the contents of file has changed. |
"ComparisonMethod" | "LastModificationDate" | method for deciding whether the file has changed, requiring a new import and cache |
"ForceImport" | False | override the cache, forcing the file to be re-imported. |
ImportOnce behaves the same as Import:
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But if you use it again on the same file, and the file has not changed, it is faster:
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Change the method for deciding if a file has changed:
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If you have reason to believe that the file has changed in a way that is not detected by your choice of "ComparisonMethod", you can force a refresh with "ForceImport"→True:
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ImportOnce can only pre-check file changes for local files. Importing over http or https will always import the file again:
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Wolfram Language 11.3 (March 2018) or above
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