WOLFRAM

Wolfram Language & System Documentation Center
Wolfram Language Home Page »

$ContextAliases
✖
$ContextAliases

✖

is a global variable that gives an association with mappings from aliases to contexts.

Details

  • $ContextAliases takes the form <|"alias1`""context1`","alias2`""context2`",…|>, where aliasi can be any string of characters that could be used to create a legal symbol name. contexti must be a fully qualified context name.
  • An alias can be used in place of a fully qualified context when referring to symbols. For a given symbol context`symbol, the name alias`symbol may be used in its place.
  • $ContextAliases can be modified directly. It is also updated automatically by calls to Needs, EndPackage and End. »

Examples

open allclose all

Basic Examples  (1)Summary of the most common use cases

Define a symbol in a specific context:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-bqewt9

Create an alias for Context1`Context2`:

In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-hlqlfy

Use the alias to reference the symbol:

In[3]:=3
✖
https://wolfram.com/xid/0k8f69axe6vn4-bsmz8d
Out[3]=3

Delete the alias:

In[4]:=4
✖
https://wolfram.com/xid/0k8f69axe6vn4-bsaerh

Scope  (8)Survey of the scope of standard use cases

Creating Context Aliases  (4)

$ContextAliases must be an association with entries of the form "alias""context`":

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-q5jyek
Out[1]=1

Aliases cannot represent relative contexts:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-cq86x8
Out[1]=1

Aliases must form legal symbol names:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-k3002q
Out[1]=1
In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-wwf85
Out[2]=2

Needs can create a context alias:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-dgmjay
Out[1]=1

Use PackedArrayQ from the Developer Utilities Package:

In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-tvxc4w
Out[2]=2

Since "Developer`" is not on $ContextPath, the unqualified symbol name is not resolved:

In[3]:=3
✖
https://wolfram.com/xid/0k8f69axe6vn4-u52nfs
Out[3]=3

Using Context Aliases  (4)

Aliases are resolved before creating new symbols:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-fn28jq
Out[2]=2

An alias may represent multiple levels of contexts:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-ba9hw1
Out[1]=1

All ways of typing in a symbol respect context aliases:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-l7gwa0
Out[1]=1

Clear a single alias:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-psnu8n
Out[1]=1

Clear all context aliases:

In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-3g8hdm
Out[2]=2

Properties & Relations  (9)Properties of the function, and connections to other functions

Context aliases work in ToExpression:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-z8uy7
Out[3]=3

A context alias is resolved in held evaluations:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-lf3zr0
Out[1]=1

Symbol resolves context aliases:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-8ofh6
Out[1]=1
Out[1]=1

Changes made to aliases after BeginPackage will be restored after the matching EndPackage:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-c4es0g
Out[1]=1

End restores $ContextAliases to the value it had before the matching Begin:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-hex3sg
Out[1]=1

Names resolves context aliases by default:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-ljn3oy
Out[1]=1

Use the ResolveContextAliases option to prevent alias resolution:

In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-iz9cwc
Out[2]=2

NameQ behaves identically:

In[3]:=3
✖
https://wolfram.com/xid/0k8f69axe6vn4-4rb3j9
Out[3]=3

Contexts resolves aliases by default:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-cgcx4w
Out[1]=1

Use the ResolveContextAliases option to prevent alias resolution:

In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-g3z0kk
Out[2]=2

Information resolves aliases by default:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-mnz331
Out[1]=1

Information also uses aliases when resolving string patterns:

In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-pa9wp7
Out[2]=2

Use the ResolveContextAliases option to prevent alias resolution:

In[3]:=3
✖
https://wolfram.com/xid/0k8f69axe6vn4-kg1st
Out[3]=3

An active alias cannot be added to $ContextPath:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-djtr67
Out[1]=1

Possible Issues  (1)Common pitfalls and unexpected behavior

Aliases can mask existing contexts:

In[1]:=1
✖
https://wolfram.com/xid/0k8f69axe6vn4-szvg2i
In[2]:=2
✖
https://wolfram.com/xid/0k8f69axe6vn4-j0zxgz
Out[2]=2

Because of the aliases, the symbol cont`x is not accessible:

In[3]:=3
✖
https://wolfram.com/xid/0k8f69axe6vn4-pl0rlf
Out[3]=3

Removing the clashing alias will restore access to the masked context:

In[4]:=4
✖
https://wolfram.com/xid/0k8f69axe6vn4-srm7uh
In[5]:=5
✖
https://wolfram.com/xid/0k8f69axe6vn4-h6lj32
Out[5]=5
Wolfram Research (2021), $ContextAliases, Wolfram Language function, https://reference.wolfram.com/language/ref/$ContextAliases.html.
✖
Wolfram Research (2021), $ContextAliases, Wolfram Language function, https://reference.wolfram.com/language/ref/$ContextAliases.html.

Text

Wolfram Research (2021), $ContextAliases, Wolfram Language function, https://reference.wolfram.com/language/ref/$ContextAliases.html.

✖
Wolfram Research (2021), $ContextAliases, Wolfram Language function, https://reference.wolfram.com/language/ref/$ContextAliases.html.

CMS

Wolfram Language. 2021. "$ContextAliases." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/$ContextAliases.html.

✖
Wolfram Language. 2021. "$ContextAliases." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/$ContextAliases.html.

APA

Wolfram Language. (2021). $ContextAliases. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/$ContextAliases.html

✖
Wolfram Language. (2021). $ContextAliases. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/$ContextAliases.html

BibTeX

@misc{reference.wolfram_2025_$contextaliases, author="Wolfram Research", title="{$ContextAliases}", year="2021", howpublished="\url{https://reference.wolfram.com/language/ref/$ContextAliases.html}", note=[Accessed: 25-May-2025 ]}

✖
@misc{reference.wolfram_2025_$contextaliases, author="Wolfram Research", title="{$ContextAliases}", year="2021", howpublished="\url{https://reference.wolfram.com/language/ref/$ContextAliases.html}", note=[Accessed: 25-May-2025 ]}

BibLaTeX

@online{reference.wolfram_2025_$contextaliases, organization={Wolfram Research}, title={$ContextAliases}, year={2021}, url={https://reference.wolfram.com/language/ref/$ContextAliases.html}, note=[Accessed: 25-May-2025 ]}

✖
@online{reference.wolfram_2025_$contextaliases, organization={Wolfram Research}, title={$ContextAliases}, year={2021}, url={https://reference.wolfram.com/language/ref/$ContextAliases.html}, note=[Accessed: 25-May-2025 ]}