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BeginPackage

Status: Stable

documented, exercised by the test suite and/or worked examples, with no known limitations recorded.

Description

BeginPackage["ctx"] sets the current context to "ctx" and restricts

BeginPackage["ctx", {"need1", ...}] additionally prepends the

Notes $ContextPath to {"ctx\`", "System\`"}, matching the standard package prologue. listed contexts to $ContextPath.

Examples (4)

Every input below was run against the current Mathilda build and its output recorded.

Applications (4)

In[1]:= $Context
Out[1]= "Global`"

In[2]:= BeginPackage["MyPkg`"]
Out[2]= "MyPkg`"

In[3]:= $Context
Out[3]= "MyPkg`"

In[4]:= $ContextPath
Out[4]= {"MyPkg`", "System`"}

Implementation notes

builtin_begin_package (src/context.c) accepts "ctx"and an optionalNeedslist of context strings, dispatching tocontext_begin_package. That pushes aFRAME_PACKAGEframe (snapshotting context and path), setsg_currentto the absolute package context (relative ``... ` contexts are rejected), clears the search path and rebuilds it as{ctx, System}plus any valid, non-duplicateNeedsentries.republish_statethen republishes$Context/$ContextPath, and the new context is returned.EndPackage[](context_end_package) pops the frame and prepends the closed context to$ContextPath. Invalid specs emitBeginPackage::cxt`.

Attributes: Protected.

References

Notes & additional examples

Notes

BeginPackage["ctx"]sets$Contexttoctx` and restricts$ContextPathto{"ctx", "System"}, matching the standard package prologue so only system symbols and the package's own symbols resolve under short names. Use the matchingEndPackage[]` to close it.