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You know the famous quote about regular expressions?

Some people, when confronted with a problem, think "I know, I'll use regular expressions." Now they have two problems. — Jamie Zawinski

Good one.

Actually even if the former is solved, the latter remains. These suckers are tough to maintain because they're not exactly self-documenting. They remind me of APL programming.

I remember APL, beer usually makes it go away as I didn't have to actually use it, just read the code.

How Does APL Compare with other Languages?

APL is a very concise language. It is normal for APL programs to have one-fifth as many instructions as programs written in other languages, and one-tenth to one-twentieth the number of instruction lines. Among the reasons for this is that APL is a symbolic language, and single symbols often replace multiple lines of code. Here is a simple comparison of a numerical sort in BASIC, FORTRAN, and APL:

BASIC
----------------------------
10 DIM X(100), (100)
20 READ N
30 FOR I =1 TO N
40 READ X(I)
50 NEXT I
60 FOR I=1 TO N
70 LET A=X(I)
80 LET L=1
90 FOR J=1 TO 10
100 IF A<X(J) THEN 130
110 LET A=X(J)
120 LETL=J
130 NEXT J
140 LET Y(I)=A
150 LET X(L)=1000000.
160 PRINT Y(I)
170 NEXT I
180 DATA
...
...
...
XXX END


FORTRAN
--------------------------------
DIMENSION X(100),Y(100)
READ(5,10) N,(X(I),I=1,N)
10 FORMAT (15/(F10.2))
DO 20 I=1,N
A=X(I)
L=1
DO 15 J=1,N
IF(A-X(J))15,15,12
12 A=X(j)
L=J
15 CONTINUE
Y(I)=A
20 X(L)=100000.
WRITE(6,30) (Y(I),I=1,N)
30 FORMAT(E15.2)
END

APL
-----


Or a fully functional game of Conway's Life in APL

stan_qaz wrote: Or a fully functional game of Conway's Life in APL

I remember that one! I think my version had three lines ... but couldn't figure out what I had done when I came back to it several weeks later. I actually programmed Life in several languages to get familiar with the coding methods.

Back to APL, while I was going to college, some of the computer sciences types had a contest to get the code down to one line for translating base 10 numbers into Roman Numerals. I chimed in with a version but was floored by someone's version that did it in a single line.

I recall that the computer center had several Selectric typewriters and I spent hours delving into APL nuances using up reams of trees. I now see that APL lives on so I'll have to check into this again ... now that fewer trees are needed.

You guys are giving your ages away. I remember working on IBM 650 computers. On them the O/S had to be loaded for every job in the form of 80 column cards.

Oh yeah!! The good old days when we were in intimate contact with our computers .... and GOTO instructions were the only way to get things done.