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YAPC::EU 2018 Glasgow Update!

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Ingy döt Net 2018-08-17 15:15:24 +01:00
parent 22f33d4004
commit 4e2d22a71d
1170 changed files with 15042 additions and 3047 deletions
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20
Task/Binary-strings/Forth/binary-strings-1.fth
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@ -9,8 +9,8 @@
: STRLEN ( addr -- length) c@ ; \ alias the "character fetch" operator
: COUNT ( addr -- addr+1 length) \ returns the address+1 and the length byte on the stack
dup strlen swap 1+ swap ;
: COUNT ( addr -- addr+1 length) \ Standard word. Shown for explanation
dup strlen swap 1+ swap ; \ returns the address+1 and the length byte on the stack
: ENDSTR ( str -- addr) \ calculate the address at the end of a string
COUNT + ;
@ -25,10 +25,10 @@
>r COUNT R> APPEND ;
: PLACE ( addr1 len addr2 -- ) \ addr1 and length, placed at addr2 as counted string
2dup 2>r 1+ swap move 2r> c! ;
2dup 2>r char+ swap move 2r> c! ;
: STRING, ( addr len -- ) \ compile a string at the next available memory (called 'HERE')
here over 1+ allot place ;
here over char+ allot place ;
: APPEND-CHAR ( char string -- ) \ append char to string
dup >r count dup 1+ r> c! + c! ;
@ -72,12 +72,12 @@
string: strpad \ general purpose storage buffer
: substr ( string1 start length -- strpad) \ Extract a substring of string and return an output string
strpad ="" \ clear strpad
>r \ push the length
+ \ calc the new start addr
r> strpad append \ pop the length and append to strpad
strpad ; \ return the address of strpad.
>r >r \ push start,length
count \ compute addr,len
r> 1- /string \ pop start, subtract 1, cut string
drop r> \ drop existing length, pop new length
strpad place \ place new stack string in strpad
strpad ; \ return address of strpad
\ COMPARE takes the 4 inputs from the stack (addr1 len1 addr2 len2 )
\ and returns a flag for equal (0) , less-than (1) or greater-than (-1) on the stack