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<cky>ArneBab_: Just one small comment. It should be "a SRFI" and not "an SRFI".

<cky>See the bottom item in http://srfi.schemers.org/srfi-faq.html

<nalaginrut>ArneBab_: well, you see the highlight

<nalaginrut>syntax highlight

***ceverett is now known as _zxq9_

<slucx>(string-set! "hello" 0 #\\A) => string is read-only

<slucx>and why?

<slucx>- Scheme Procedure: string-set! str k chr

<slucx> Store CHR in element K of STR and return an unspecified value. K

<slucx> must be a valid index of STR.

<nalaginrut>slucx: because literal string is immutable

<nalaginrut>slucx: you may generate a string with make-string

<slucx>I got it, thanks nalaginrut

<slucx>It's like C's string and char array

<nalaginrut>np ;-)

<slucx>nalaginrut: I make a string with length 1 use (define ss (make-string

<nalaginrut>sneek: later tell slucx because string-cope does a new copy

<sneek>Okay.

<mark_weaver>slucxx: string-copy takes only one string argument, and allocates a fresh new copy. it doesn't copy into an existing string.

<mark_weaver>e.g. (string-copy "hello") returns a copy of "hello" that you can now mutate

<slucxx>mark_weaver: I got it, thank you ;-)

<sneek>slucxx, you have 1 message.

<sneek>slucxx, nalaginrut says: because string-cope does a new copy

<mark_weaver>slucxx: if you pass a string as the second argument, it should raise an error. it does for me, anyway. what version of guile are you using?

<slucxx>guile-2.0

<mark_weaver>what micro version? "2.0.x" what is the x?

<slucxx>$8 = "2.0.11"

<mark_weaver>excellent!

<slucxx>string-copy just have on argument

<mark_weaver>slucxx: so now I'm confused. You asked why (string-copy ss "hello") doesn't overflow the string in 'ss'. but that should have raised an error about the second argument. Does it not raise an error for you?

<mark_weaver>I get: ERROR: In procedure string-copy: ERROR: Wrong type (expecting exact integer): "hello"

<slucxx>It's my fault, my really code is that,

<slucxx>(let ((ss (make-string 1))) (set! ss (string-copy "hello")))

<slucxx>:)

<mark_weaver>ah, okay.

<mark_weaver>that works because 'ss' is actually a pointer to a string object.

<slucxx>i think everything is point within scheme

<mark_weaver>semantically, yes, that's true.

<slucxx>ss just keep the point of new string

<mark_weaver>actually, we represent some immutable types as immediates.

<mark_weaver>e.g. small integers and characters.

<mark_weaver>but yes, you can think of everything as a pointer, and you won't go wrong.

<mark_weaver>yes, exactly, you were just setting 'ss' to point to the new string and discarding the other one.

<slucxx>mark_weaver: okay

<mark_weaver>okay, I'm off to spend some time with my family. happy hacking!

<slucxx>mark_weaver: thank you

<slucxx>from the heart

<slucxx>good night everyone

***cluck` is now known as cluck

IRC channel logs

2014-12-25.log