The 'sorta' scripts described below can sorta be found in this directory.
sorta.i2+2
----------
2 2+#` [ about as basic as you can get ]ld
This script takes 2, adds 2 to it, and prints the result (with a
newline). I get 5 on the hand-held Sinclair under ZYNIX. Let me know if
your machine produces a different result so that I can send you patches.
sorta.iarg0
-----------
0A` [ take arg 0, print it ]
This is self-explanatory.
sorta.icalc
-----------
[D2sD3s]:Dld [ input m n, output m n m n ]ld
[2*1=d]:cld [ aux routine for :d recursion ]ld
[1=D1s>1Ds_+=c]:dld [ input m n, as long as n <= m double it, output m n ]ld
[D2s1s_+1s]:-ld [ input m n, output m-n n ]ld
[1=D1s>1Ds_+#T=-2/D=1]:1ld [ aux routine for :@ ]ld
[1D=d2/1=1ddd1 ]:!ld
["0"Td]:0ld
[DD=!1_+=0]:@ld [ input m, m assumed nonnegative, append
binary representation of m to top of s stack ]ld
["-"T_]:+ld
[D0 1s>=+1=@]:2ld [ input m, append - to top of s stack if m is negative,
then append binary representation of abs(m) to
top of s stack ]ld
[d1A:A2=A]:A 27182 a1>=A
[d2A:A1=A]:A 3145 a2>=A
D # " in binary is "T 1=2 `ld
1=Dd # " in binary is "T 1=2 `ld
1=D 1s# " + "T 1s#T " is "T + #Td `ld
1=D 1s# " - "T 1s#T " is "T _+ #Td `ld
1=D 1s# " * "T 1s#T " is "T * #Td `ld
1=D 1s# " / "T 1s#T " is "T / #Td `ld
1=D 1s# " % "T 1s#T " is "T 1=D/*_+ #Td `ld
1=D d "~ " #T " is "T D& #T$ld " (" 1=2 ")"T `ld
1=D 1s# " & "T 1s#T " is "T &D& #T$ld " (" 1=2 ")"T `ld
1=D 1s# " | "T 1s#T " is "T D&1sD&& #T$ld " (" 1=2 ")"T `ld
1=D 1s# " ^ "T 1s#T " is "T 1=D&2sD&1sD&&&D& #T$ld " (" 1=2 ")"T `ld
icalc shows off SORTA's understanding of integer arithmetic. You can run
it with up to two arguments; the arguments have default values of 27182
and 3145. Notice that sorta doesn't have a language primitive for
converting a string to a number, yet icalc is performing arithmetic on
its arguments. Can you see how? (Hint: Try sorta "2 2+" 3 < sorta.icalc.
Look at program A.) icalc also provides a useful binary output routine,
and if you can't remember offhand that D2sD3s&2sD&1sD&&&D& means xor,
you can just look it up here.
sorta.idup
-----------
[ld#1_+1=y]:x
[uD1+=x]:y
0""1=y`
This script prints out the maximum file descriptor available from
repeated dup()s---usually NOFILE - 1. Can you see how it works?
sorta.iecho
-----------
[" "$ld]:sld [ print a space ]ld
[1s1+DA$ld1s1_+D=sD=x]:xld [ given n (argc-n), print args ]ld
0a1_+D=x""` [ simulation of /bin/echo ]ld
This is a clone of /bin/echo, minus any argument processing and escape
interpretation. (Note that, unlike some shells' echo, /bin/echo prints a
newline even with no arguments.) Try sorta foo bar < iecho.
sorta.ifact1
------------
1#`ld2*#`ld3*#`ld4*#`ld5*#`ld6*#`ld7*#`ld8*#`ld9*#`ld10*#`ld
This is a very straightforward factorial program: Take 1, print it,
multiply by 2, print it, multiply by 3, print it, etc.
sorta.ifact2
------------
[1+D2s*#`ld1s]:f
1 0
1=f 1=f 1=f 1=f 1=f 1=f 1=f 1=f 1=f 1=f
ifact1 does a lot of repeated work. ifact2 takes advantage of this by
keeping the current n! n on the stack. Each call to routine f (1=f)
increments n by 1 and prints out the factorial.
sorta.ifact3
------------
[1+D2s*#`ld1s]:f [ given (n-1)! (n-1), print n!, put n! n ]
[2s1=f2s1_+D0>=x]:x [ given n n! x, print (n+1)! through (n+x)! ]
0 1 10 1=x
Finally, ifact3 removes all the redundancy from ifact2, and exhibits
proper documentation of stack routines. You can replace the 10 by
anything in this version.
sorta.iio
---------
[ a simple example of interpreting code on the fly ]ld
["] "2 2+":xT ["]T " produces "T 1=x#T " which should be 4."T`
Notice that "2 2+" is a literal string inside the program.
sorta.irot13
------------
"[] [.tr] "
["]".[a-m][n-z][A-M][N-Z]"[" ]TTT ["]".[n-z][a-m][N-Z][A-M]"[" ]TTT
"[tr] !q"T:xld
["rot13: fatal: need exactly one argument"`q]:gld
["rot13: fatal: cannot open "1ST`q]:hld
a2_+=g
1A 0 [ that 0 is for RDONLY ]ld
0 'o D0 1s>=hld
0Ou1=x [ in a more complex spawner, this would be done under a fork ]ld
Despite its name, irot13 is meant to show how to exec a program with
redirection from within sorta. You run it as sorta blah < irot13; it
opens blah and runs a (BSD-style) tr command to rotate all letters by 13
spots. 1A 0 0 o opens argv[1]; the ' keeps the filename around for
subroutine h to print a nice error message if necessary. 0Ou closes
stdout and replaces it with the new descriptor. Finally, subroutine x
executes the tr.
sorta.isleep
------------
["" "+sleep" "+5" "sleep" !q]:S [F0>1_+=S]:s
"forking sleep 5..."`ld
1=s
"waiting for sleep to finish..."`ld
w
"done, sleep exit code " #T`
This script illustrates the classic fork-exec-wait.
sorta.itailrec
--------------
[3*#" "T$ldD=f]:f
1=f
The sole purpose of this script is to prove that sorta can do infinite
tail recursion (in this case, in program f). Do sorta < itailrec | more
and watch the powers of 3 (mod your computer's word size) flow by.
sorta.iwhosort
--------------
[0Ou "" "+-u" "sort" !q]:S [F0>1_+=S]:s
[1Ou "" "+-u" "who" !q]:W [F0>1_+=W]:w
P1=wO1=sOww
This final example is a simple pipeline, who | sort.