System Function EM

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⎕EM - Error Message

⎕EM Return the value of the current error message

⎕EM is an ISO/IEC 13751 standard niladic system function which returns the current error message. This is a character matrix of three rows. The first row is the text of the error message itself. The second row is the line typed in or the line of the function where the error occurred. The third row is usually a caret () pointing to where the error in the line shown in the second element occurred.

The format of ⎕EM is implementation dependent. Here is an example from NARS2000 on an attempt to make 2+2 = 5:

      5←2+2 
SYNTAX ERROR 
      5←2+2 
       ∧ 
      ⎕EM 
SYNTAX ERROR 
      5←2+2 
       ∧
      ⍴⎕EM
3 12


Note: EM is a niladic form system function, you cannot assign a value to it.

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


See Also
System Commands System Variables and Functions Operators


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