Function Repository Resource:

UnformalizeSymbols

Source Notebook

Convert formal symbols in an expression into non-formal versions

Contributed by: Paco Jain (Wolfram Research)

ResourceFunction["UnformalizeSymbols"][expr]

converts all formal symbols in expr to their non-formal counterparts.

Details and Options

ResourceFunction["UnformalizeSymbols"] only replaces formal symbols from the System` context.

ResourceFunction["UnformalizeSymbols"] takes the following options:

"DeferQ"

False

whether to wrap replaced symbols in Defer

"TargetContext"

Automatic

the context to place converted symbols into

By default, formal symbols are converted to non-formal symbols in the current context, as given by $Context. To place output symbols into another context, use the option "TargetContext".

Examples

Basic Examples (3)

Convert formal symbols to their non-formal counterparts:

In[1]:=

$ResourceFunction["UnformalizeSymbols"][\[FormalA] + \[FormalB]]$

Out[1]=

UnformalizeSymbols works on Latin, Greek and other symbols for which there exists a formal version in the Wolfram Language:

In[2]:=

$ResourceFunction["UnformalizeSymbols"][\[FormalPhi]/8]$

Out[2]=

In[3]:=

$ResourceFunction["UnformalizeSymbols"][Cos[\[FormalSampi]]]$

Out[3]=

UnformalizeSymbols works on both uppercase and lowercase letters:

In[4]:=

$ResourceFunction[ "UnformalizeSymbols"][(\[FormalR]/\[FormalCapitalA]) \[FormalLambda] + \[FormalCapitalLambda]]$

Out[4]=

Options (4)

DeferQ (2)

By default, symbols in the output of UnformalizeSymbols may ultimately evaluate, should they have definitions. Here, a has a value in "Global`" and so does not appear in the final result:

In[5]:=

$a = 2; ResourceFunction["UnformalizeSymbols"][\[FormalA] + \[FormalB]]$

Out[5]=

With the setting "DeferQ"→ True, replaced symbols are wrapped in Defer prior to output, preventing their evaluation until given explicitly as input (using , Evaluate in Place, etc.):