System Function LC

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⎕LC - Line Counter

⎕LC is an ISO/IEC 13751 standard niladic system function which returns an integer vector of the current line numbers being executed in every current function. Consider the following functions:

    ∇ test
[1]   'LC=',⎕LC
    ∇

    ∇ test2
[1]   'Calling test'
[2]   test
    ∇

So the following commands would produce the following output:

      test
LC= 1
      test2
Calling Test
LC= 1 2

In the first example where the function test is invoked, only function test is executing so a one-element vector - the current line number of test that is being executed - is shown. In the second example where the function test2 is invoked, the APL interpreter program is currently executing line 1 of function test, which was called by line 2 of test2, thus a two-element vector of values 1 and 2 is displayed.


Note: LC 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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