Okay guys, this is probably an easy one for you. I'm afraid I'm missing
something fundamental with regard to indexed strings and until clauses.
I've reduced my program to the the following fragment in which the loop
never terminates:
trace results
parse source . . me .
file = BufferedReader(FileReader(me))
rec = ''
loop i = 1 until rec[i] = null
rec[i] = file.readLine()
end i
say rec[i-1]
The salient portion of the trace shows that rec[i] never matches null:
6 *=* rec[i] = file.readLine()
>>> "7"
>v> rec "end i"
5 *=* loop i = 1 until rec[i] = null
>>> "7"
>>> "0"
>v> i "8"
6 *=* rec[i] = file.readLine()
>>> "8"
>v> rec [null]
5 *=* loop i = 1 until rec[i] = null
>>> "8"
>>> "0"
>v> i "9"
Falling back to a working example, I tried reading the line into a simple
variable, then assigning that variable to the indexed variable:
trace results
parse source . . me .
file = BufferedReader(FileReader(me))
rec = ''
loop i = 1 until line = null
line = file.readLine()
rec[i] = line
end i
say rec[i-1]
.. which gave me the following NetRexx error:
5 +++ loop i = 1 until line = null
+++ ^^^^
+++ Error: Unknown variable
.. which I fixed by initializing 'line':
trace results
parse source . . me .
file = BufferedReader(FileReader(me))
rec = ''
line = ''
loop i = 1 until line = null
line = file.readLine()
rec[i] = line
end i
say rec[i-1]
.. which works, but leaves me with two questions:
1. Why did the until clause comparison fail with an indexed variable?
2. Why must I initialize an until clause variable that is assigned in the
body of the loop?
I'm running the OS/2 JDK 1.1.1 with NetRexx 1.113, if it matters.
-Chip Davis- Aresti Systems Member of: Rexx Language Association
[hidden email] P.O.Box 13306 ANSI Rexx Standard Committee
919.303.3306 RTP NC 27709-3306 TeamOS/2 & Thoroughly Warped!
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