**//Input and output//**

LabLISP in the present state is somewhat limited when it comes to input and output. It is developed as scripting language for other programs and most of its iteractions with outside world are done through the LabLispHost system.

''READ''

Takes one string argument and passes it to the reader algorithm. Produces Lisp objects. Without having explicit ''EVAL'' function, the ''READ'' is just good for testing the reader behavior.

<code lisp>
>(read "`(+ ,a ,b)")
(BACKQUOTE (+ (UNQUOTE A) (UNQUOTE B)))
</code>

see also ''LOAD''

''PRINT''

Takes one argument and passes it to the printer algorithm. Returns the argument back, but as a side effect, also prints it.

<code lisp>
>(progn 
   (print 'a)
   (print 'b) 
   (print 'c))
A
B
C
C                 ; return from the last PRINT
</code>

''WRITE-TO-STRING''

Takes one argument and passes it to printer. Returns the string representation of the object.

<code lisp>
>(write-to-string '(+ 1 3))
"(+ 1 3)"
</code>

''CONCATENATE''

Takes any number of arguments, at least one. Converts them to strings as with ''WRITE-TO-STRING'' and concatenates to one string.

<code lisp>
>(concatenate 'id (+ 1 2) " tag")
"ID3 tag"
</code>


''TIME-STAMP''

Produces string with actual date and time. Takes zero or one argument, the argument is optional formatting string, passed directly to ''QDateTime::toString()''. Use yy or yyyy for year, MM for month number, or MMM for month name, dd for day number, and hh:mm:ss.zzz for hours, minutes, seconds and milliseconds. Single t shows the time-zone.

<code lisp>
>(time-stamp)
"2024-05-04 19:18:41"                 ; standard date time format
>(time-stamp "hh:mm:ss.zzz t")
"19:28:37.412 W. Europe Summer Time"  ; time including milliseconds, timezone
>(time-stamp "MMM-dd")
"May-04"                              ; may the fourth ....
</code>