14f is a forth-like language inspired by uxn. It's interpreted and runs in the browser. Its main goal is to be simple to understand and fun to use.
At the heart of 14f there is a stack. We can push numbers to the stack. Let's push number 1 and number 2:
#1 #2
The interpreter reads the previous line from left to right. It first pushes #1 to the stack, then #2. Once the line has been interpreted, the stack looks like that:
1 2
We can operate on the stack by using words. To add the top 2 elements from the stack, we can use "+".
+
The stack now contains only "3", since 1 and 2 have been added. This is how 14f works. Numbers are pushed on the stack, and words operate on these numbers to produce interesting results.
All numbers are expressed in hexadecimal. To push a number on the stack, prefix it with #. For example, to push the number 15 on the stack, type: #f.
Words operate on the stack. All the basic words are defined in the glossary, and can be combined by creating entries in the dictionary. To create an entry, use the ":" word:
: foo #1 #2 + ;
The previous like creates a "foo" entry in the dictionary. We can now use foo by just typing it.
Special syntax that aren't words nor numbers.
Use "if" to create a branch based on a condition. The following line will push #1 to the stack if ?ready is equal to 1, otherwise it will push #2.
?ready if #1 else #2 then
Push to the stack the address of the following word.
' foo
Loop until the top of the stack is 0.
' eat until
| word | stack | definiton |
|---|---|---|
| + | n1 n2 -- n1+n2 | Add the top 2 elements from the stack |
| - | n1 n2 -- n1-n2 | Substract the top 2 elements from the stack |
| * | n1 n2 -- n1*n2 | Multiply the top 2 elements from the stack |
| / | n1 n2 -- n1/n2 | Divide the top 2 elements from the stack |
| % | n1 n2 -- n1%n2 | Modulo of the top 2 elements from the stack |
| drop | n -- | Drop the top of the stack |
| = | n1 n2 -- f | Push #1 if n1 and n2 are equal, #0 otherwise |
| > | n1 n2 -- f | Push #1 if n1 > n2, #0 otherwise |
| < | n1 n2 -- f | Push #1 if n1 < n2, #0 otherwise |
| and | f1 f2 -- f | Push #1 if f1 and f2 are true, #0 otherwise |
| , | n -- | Record n to the memory |
| @ | adr -- n | Push value from adr to the stack |
| ! | n adr -- | Record n at adr |
| d@ | adr -- n | Push value from system adr to the stack |
| d! | n adr -- | Record n at system adr |
| dup | n -- n n | Duplicate the top of the stack |
| swap | n1 n2 -- n2 n1 | Swap the top of the stack |
| rot | n1 n2 n3 -- n2 n3 n1 | Rotate the top of the stack |
| rect | w h c -- | Draw w*h rect of color c |
| clear | -- | Clear screen |
| sprite | adr -- | Draw 2bpp sprite at adr |
| rand | min max -- n | Push random n in [min max] |