Data commit

Task/Gotchas/J/gotchas-1.j

@@ -0,0 +1,10 @@
+   ex1=: 1 2 3 4 5
+   ex2=: '1 2 3 4 5'
+   ex1
+1 2 3 4 5
+   ex2
+1 2 3 4 5
+   10+ex1
+11 12 13 14 15
+   10+ex2
+|domain error

Task/Gotchas/J/gotchas-2.j

@@ -0,0 +1,8 @@
+   1 2 3 + 4 5 6
+5 7 9
+   +/ 1 2 3 + 4 5 6
+21
+   1 2 3 +/@:+ 4 5 6
+21
+   1 2 3 +/@+ 4 5 6
+5 7 9

Task/Gotchas/J/gotchas-3.j

@@ -0,0 +1,6 @@
+   10 100 1000 +/ .*1 2 3  NB. vector multiplication
+3210
+   10 100 1000 +/.*1 2 3   NB. complex conjugate of signum of right argument grouped by the left argument
+1
+1
+1

Task/Gotchas/J/gotchas-4.j

@@ -0,0 +1,11 @@
+   A=: 2 3 5 7 11    NB. legal
+   B=: 999           NB. legal
+   B 0} A            NB. functional array update (does not change A)
+   NB. the use of a single brace to denote indexing might also confuse people
+999 3 5 7 11
+   0} A              NB. legal
+2
+   999 0} A          NB. not legal
+|rank error
+   (999)0} A         NB. what was intended
+999 3 5 7 11

Task/Gotchas/J/gotchas-5.j

@@ -0,0 +1,14 @@
+   0x100   NB. 0*e^100 where e is the natural logarithm base 2.71828...
+0
+   0xff
+|ill-formed number
+   16b100 16bff
+256 255
+   8ad90   NB. 8 on the complex plane at an angle of 90 degrees from the real axis
+0j8
+   -100   NB. two tokens
+_100
+   _100+10   NB. three tokens
+_90
+   -100+10   NB. four tokens
+_110

Task/Gotchas/J/gotchas-6.j

@@ -0,0 +1,4 @@
+   1+2*3   NB. processed right-to-left
+7
+   2*3+1   NB. processed right-to-left
+8