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Diffstat (limited to 'forth.html.markdown')
| -rw-r--r-- | forth.html.markdown | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/forth.html.markdown b/forth.html.markdown index f7c0bf34..ff094017 100644 --- a/forth.html.markdown +++ b/forth.html.markdown @@ -12,7 +12,7 @@ such as Open Firmware. It's also used by NASA. Note: This article focuses predominantly on the Gforth implementation of Forth, but most of what is written here should work elsewhere. -``` +```forth \ This is a comment ( This is also a comment but it's only used when defining words ) @@ -54,12 +54,12 @@ Forth, but most of what is written here should work elsewhere. 3 dup - \ duplicate the top item (1st now equals 2nd): 3 - 3 2 5 swap / \ swap the top with the second element: 5 / 2 6 4 5 rot .s \ rotate the top 3 elements: 4 5 6 -4 0 drop 2 / \ remove the top item (dont print to screen): 4 / 2 +4 0 drop 2 / \ remove the top item (don't print to screen): 4 / 2 1 2 3 nip .s \ remove the second item (similar to drop): 1 3 \ ---------------------- More Advanced Stack Manipulation ---------------------- -1 2 3 4 tuck \ duplicate the top item into the second slot: 1 2 4 3 4 ok +1 2 3 4 tuck \ duplicate the top item below the second slot: 1 2 4 3 4 ok 1 2 3 4 over \ duplicate the second item to the top: 1 2 3 4 3 ok 1 2 3 4 2 roll \ *move* the item at that position to the top: 1 3 4 2 ok 1 2 3 4 2 pick \ *duplicate* the item at that position to the top: 1 2 3 4 2 ok @@ -117,7 +117,7 @@ one-to-12 \ 0 1 2 3 4 5 6 7 8 9 10 11 12 ok : threes ( n n -- ) ?do i . 3 +loop ; \ ok 15 0 threes \ 0 3 6 9 12 ok -\ Indefinite loops with `begin` <stuff to do> <flag> `unil`: +\ Indefinite loops with `begin` <stuff to do> <flag> `until`: : death ( -- ) begin ." Are we there yet?" 0 until ; \ ok \ ---------------------------- Variables and Memory ---------------------------- @@ -133,7 +133,7 @@ variable age \ ok age @ . \ 21 ok age ? \ 21 ok -\ Constants are quite simiar, except we don't bother with memory addresses: +\ Constants are quite similar, except we don't bother with memory addresses: 100 constant WATER-BOILING-POINT \ ok WATER-BOILING-POINT . \ 100 ok |