System Function VR

Z←⎕VR R returns the visual representation of the user-defined function or operator named in R.

R is a character scalar or vector.

Z is a character vector representation of the user-defined function/operator.

This function is implemented via the Magic Function #MonVR.

For example,

      ⎕VR '#MonVR'
    ∇ Z←#MonVR R;⎕io
[1]   ⎕io←0
[2]   Z←1 ⎕cr R
[3]   →(0≠⍴Z)/L1 ⋄ Z←'' ⋄ →0
[4]   L1:→(1=≡Z)/0
[5]   Z←(∊((⊂[1]'LO<    ∇>P<[>Q<]>I6' ⎕fmt ⍳⍴Z),¨Z),¨⊂⎕TCNL,⎕TCLF),'    ∇'
    ∇

If the function named in R is directly assigned, the result is the character vector representation of that function (see line 4 above), as in

      f←+.×
      ⍴⎕←⎕vr 'f'
+.×
3

System Variables (A value may be assigned to these except for ⎕DM)
⎕ALX	⎕CT	⎕DM	⎕DT	⎕ELX	⎕FC	⎕FEATURE	⎕FPC	⎕IC	⎕IO
⎕LR	⎕LX	⎕PP	⎕PR	⎕PW	⎕RL	⎕SA	⎕WSID
Niladic System Functions (a value cannot be assigned to these)
⎕A	⎕AV	⎕EM	⎕ET	⎕LC	⎕NNAMES	⎕NNUMS	⎕SI	⎕SYSID	⎕SYSVER
⎕T	⎕TC	⎕TCBEL	⎕TCBS	⎕TCESC	⎕TCFF	⎕TCHT	⎕TCLF	⎕TCNL	⎕TCNUL
⎕TS	⎕WA
Monadic or dyadic system functions (a value cannot be assigned to these)
⎕AT	⎕CR	⎕DC	⎕DFT	⎕DL	⎕DR	⎕EA	⎕EC	⎕ERROR	⎕ES
⎕EX	⎕FMT	⎕FX	⎕MF	⎕NAPPEND	⎕NC	⎕NCREATE	⎕NERASE	⎕NINFO	⎕NL
⎕NLOCK	⎕NREAD	⎕NRENAME	⎕NREPLACE	⎕NRESIZE	⎕NSIZE	⎕NTIE	⎕NUNTIE	⎕STOP	⎕TF
⎕TRACE	⎕UCS	⎕VR
Note that quad functions and variables (except for the ⎕A family of functions) are case insensitive