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End

Status: Stable

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

Description

End[]

restores the context that was active before the matching Begin[]

Notes and returns the closed context as a string.

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]:= Begin["foo`"]
Out[2]= "foo`"

In[3]:= End[]
Out[3]= "foo`"

In[4]:= $Context
Out[4]= "Global`"

Implementation notes

builtin_end (0-arg) calls context_end, which pops the top frame of the context stack (g_stack, a linked list of CtxFrame pushed by Begin/BeginPackage). frame_pop restores $Context (g_current) and the $ContextPath snapshot (saved_path) that the matching Begin[] saved, frees the popped frame, and republishes the live state. The builtin returns the closed context string (the one that was current just before the pop). If the stack is empty it emits End::noctx and returns NULL (unevaluated). Context names are owned as plain char* via the file's ctx_strdup (a C99-safe strdup replacement).

Attributes: Protected.

References

Notes & additional examples

Notes

End[] closes the context opened by the matching Begin[], restoring the previously active $Context and returning the context it just closed as a string.