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As of Version 12.2, the "Package" format has been superseded by the "WL" format.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 reference pages for full general information on Import and Export.
    • ImportString and ExportString support the package format.

    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"full list of rules for each element and option
      "Options"list of rules for options, properties, and settings
    • 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.

    Options

    Examples

    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: