System Function TF

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⎕TF - Transfer Function

Z←L ⎕TF R If R is the name of an object in the workspace, returns the transfer form of R, or if R already represents a transfer form, converts it into an object in the workspace.
L is an integer scalar or one-element vector.
R is a character scalar or vector.
If R is the name of an object in the workspace, Z is a character vector of the transfer form of R, or if R is a transfer form, Z is a character vector of the name of the object converted into the workspace.


The left argument may be one of the values ¯2, ¯1, 1, or 2. The absolute value of the left argument indicates the type of transfer (1 or 2 as described in the Extended APL Standard) produced as a result or established in the workspace. The sign of the left argument indicates whether or not the argument is translated to/from the APL2 character set; a positive left argument performs the translation, a negative argument does not. Not translating the argument allows the NARS symbols (e.g., , , etc.) not in the APL2 character set to be represented.

Note that as a consequence of this, neither 1 ⎕TF nor 2 ⎕TF on the name of a system variable (e.g., 1 ⎕TF '⎕IO') works because the right argument is first translated into the APL2 character set which changes the quad symbol in the NARS character set into something else in the APL2 character set. Either use a left argument of ¯1 or ¯2, or a right argument which starts with ⎕AV[144+⎕IO], which is Quad in the APL2 character set back translated into the NARS character set.

See Proposal To Extend .atf Files for an alternate view of how this function might work.

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