From 68fb553332f582f5f910fd346e0dd4de80346d67 Mon Sep 17 00:00:00 2001 From: Reid Spencer Date: Wed, 4 May 2005 15:43:40 +0000 Subject: [PATCH] Correct the descriptions of WHILE...END and RROT. Thanks to Lalo Martins for pointing out these errors. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21683 91177308-0d34-0410-b5e6-96231b3b80d8 --- docs/Stacker.html | 38 +++++++++++++++++++++----------------- 1 file changed, 21 insertions(+), 17 deletions(-) diff --git a/docs/Stacker.html b/docs/Stacker.html index 04b796b1122..bdd41bbfe59 100644 --- a/docs/Stacker.html +++ b/docs/Stacker.html @@ -787,7 +787,7 @@ using the following construction:

RROT RROT - w1 w2 w3 -- w2 w3 w1 + w1 w2 w3 -- w3 w1 w2 Reverse rotation. Like ROT, but it rotates the other way around. Essentially, the third element on the stack is moved to the top of the stack. @@ -946,24 +946,28 @@ using the following construction:

executed. In either case, after the (words....) have executed, execution continues immediately following the ENDIF. -WHILE (words...) END - WHILE (words...) END +WHILE word END + WHILE word END b -- b - The boolean value on the top of the stack is examined. If it is non-zero then the - "words..." between WHILE and END are executed. Execution then begins again at the WHILE where another - boolean is popped off the stack. To prevent this operation from eating up the entire - stack, you should push on to the stack (just before the END) a boolean value that indicates - whether to terminate. Note that since booleans and integers can be coerced you can - use the following "for loop" idiom:
- (push count) WHILE (words...) -- END
+ The boolean value on the top of the stack is examined (not popped). If + it is non-zero then the "word" between WHILE and END is executed. + Execution then begins again at the WHILE where the boolean on the top of + the stack is examined again. The stack is not modified by the WHILE...END + loop, only examined. It is imperative that the "word" in the body of the + loop ensure that the top of the stack contains the next boolean to examine + when it completes. Note that since booleans and integers can be coerced + you can use the following "for loop" idiom:
+ (push count) WHILE word -- END
For example:
- 10 WHILE DUP >d -- END
- This will print the numbers from 10 down to 1. 10 is pushed on the stack. Since that is - non-zero, the while loop is entered. The top of the stack (10) is duplicated and then - printed out with >d. The top of the stack is decremented, yielding 9 and control is - transfered back to the WHILE keyword. The process starts all over again and repeats until - the top of stack is decremented to 0 at which the WHILE test fails and control is - transfered to the word after the END. + 10 WHILE >d -- END
+ This will print the numbers from 10 down to 1. 10 is pushed on the + stack. Since that is non-zero, the while loop is entered. The top of + the stack (10) is printed out with >d. The top of the stack is + decremented, yielding 9 and control is transfered back to the WHILE + keyword. The process starts all over again and repeats until + the top of stack is decremented to 0 at which point the WHILE test + fails and control is transfered to the word after the END. + INPUT & OUTPUT OPERATORS -- 2.34.1