mirror of
https://github.com/adambard/learnxinyminutes-docs.git
synced 2024-12-23 09:41:36 +00:00
Capitalize instances of 'forth'.
This commit is contained in:
parent
70b03c1868
commit
4d80a56d2c
@ -20,7 +20,7 @@ Forth, but most of what is written here should work elsewhere.
|
||||
|
||||
\ --------------------------------- Precursor ----------------------------------
|
||||
|
||||
\ It's important to know how forth processes instructions. All
|
||||
\ It's important to know how Forth processes instructions. All
|
||||
\ programming in Forth is done by manipulating what's known as the parameter
|
||||
\ stack (more commonly just referred to as "the stack"). Typing:
|
||||
5 2 3 56 76 23 65
|
||||
@ -69,8 +69,8 @@ Forth, but most of what is written here should work elsewhere.
|
||||
\ Quite often one will want to write their own words.
|
||||
: square ( n -- n ) dup * ; \ ok
|
||||
|
||||
\ The `:` word sets forth into compile mode. `(` and `)` are both words which
|
||||
\ tell forth to ignore between them. Up until the `;` word is what our word
|
||||
\ The `:` word sets Forth into compile mode. `(` and `)` are both words which
|
||||
\ tell Forth to ignore between them. Up until the `;` word is what our word
|
||||
\ does.
|
||||
|
||||
\ We can check the definition of a word with the `see` word:
|
||||
@ -78,7 +78,7 @@ see square \ dup * ; ok
|
||||
|
||||
\ -------------------------------- Conditionals --------------------------------
|
||||
|
||||
\ In forth, -1 is used to represent truth, and 0 is used to represent false.
|
||||
\ In Forth, -1 is used to represent truth, and 0 is used to represent false.
|
||||
\ The idea is that -1 is 11111111 in binary, whereas 0 is obviously 0 in binary.
|
||||
\ However, any non-zero value is usually treated as being true:
|
||||
42 42 = / -1 ok
|
||||
@ -184,13 +184,13 @@ create mynumbers 64 , 9001 , 1337 , \ the last `,` is important!
|
||||
\ As well as reading, we can add to the return stack and remove from it:
|
||||
5 6 4 >r swap r> .s \ 6 5 4
|
||||
|
||||
\ NOTE: Because forth uses the return stack for word pointers, it's essential
|
||||
\ NOTE: Because Forth uses the return stack for word pointers, it's essential
|
||||
\ that you set the return stack back to how it was at the end of your
|
||||
\ definition. `>r` should always be followed by `r>`.
|
||||
|
||||
\ ------------------------- Floating Point Operations --------------------------
|
||||
|
||||
\ Most forths tend to dislike the use of floating point operations. We write
|
||||
\ Most Forths tend to dislike the use of floating point operations. We write
|
||||
\ floating point operations with scientific notation.
|
||||
8.3e 0.8e f+ f. \ 9.1 ok
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user