Package (.wl, .m)

As of Version 12.2, the "Package" format has been superseded by the "WL" format.
  • Import and Export fully support Wolfram Language package files.
  • Background & Context

      • MIME type: application/vnd.wolfram.wl, application/vnd.wolfram.mathematica.package
      • Wolfram Language package source format.
      • Used for storing and exchanging Wolfram Language programs, packages, and data.
      • Plain ASCII text format.
      • Stores Wolfram Language expressions in InputForm.
      • Can represent program code, numerical and textual data, 2D raster and vector images, 3D geometries, sound, and other kinds of data.
      • Developed since 1988 by Wolfram Research.

    Import & Export

    • Import["file.m"] reads in a Wolfram Language package, evaluating each expression in it and returning the last one.
    • Export["file.m",expr] exports a single expression to a package source file.
    • The Wolfram Language always uses CharacterEncoding->"ASCII" for package source files.
    • Import["file.m",elem] imports the specified element from a package source file.
    • Import["file.m",{elem,suba,subb,}] imports a subelement.
    • Import["file.m",{{elem1,elem2,}}] imports multiple elements.
    • The import format can be specified with Import["file","Package"] or Import["file",{"Package",elem,}].
    • Import["file.m"] is equivalent to Get["file.m"].
    • Export["file.m",expr,elem] creates a Wolfram Language source file by treating expr as specifying element elem.
    • Export["file.m",{expr1,expr2,},{{elem1,elem2,}}] treats each expri as specifying the corresponding elemi.
    • Export["file.m",expr,opt1->val1,] exports expr with the specified option elements taken to have the specified values.
    • Export["file.m",{elem1->expr1,elem2->expr2,},"Rules"] uses rules to specify the elements to be exported.
    • Put[expr1,expr2,,"file.m"] can be used to export multiple expressions.
    • See the following reference pages for full general information:
    • Import, Exportimport from or export to a file
      CloudImport, CloudExportimport from or export to a cloud object
      ImportString, ExportStringimport from or export to a string
      ImportByteArray, ExportByteArrayimport from or export to a byte array

    Notebook Interface

    • In the notebook front end, Save As can be used to export a notebook as a Wolfram Language package.

    Import Elements

    • General Import elements:
    • "Elements" list of elements and options available in this file
      "Rules"list of rules for all available elements
    • Import elements:
    • "ExpressionList"evaluates all expressions and returns the results as a list
      "Get"reads and evaluates all expressions, returning the last one
      "HeldExpressions"list of unevaluated expressions
      "InactivatedExpressions"list of inactivated expressions
      "Comments"code comments
    • Import by default uses the "Get" element for Wolfram Language package files.



    Basic Examples  (3)

    Show the Import elements available in a sample file:

    Import unevaluated expressions from this file:

    Import all expressions and run them through Inactivate:

    Import only the first expression from the package in Inactive form:

    Export an arbitrary expression to the package format:

    Import the previous output: