nappa85

nappa85

Rust Brain Teasers - How long is a String? (page 22)

The phrase

Unicode string character by character can consume a lot more memory
than  you  expected.  The  string  love: ❤  is  7  characters  long,  requires  12
bytes of storage in a String—and 32 bytes of memory when processed as
individual  characters.  This  may  seem  like  a  small  amount  of  memory,
but if your reader enters the entirety of War and Peace into your program’s
input box, per-character parsing may require more resources than you
expected

gives, in my humble opinion, the wrong idea that iterators allocate memory.
What’s written is true if I do my_string.chars().collect::<Vec<char>>(), but only iterating overs chars won’t consume any memory, the single chars are transmuted from original string bytes.
I suggest to reformulate the example clarifing that iterators won’t allocate memory

First Post!

herbert

herbert

Author of Hands-on Rust

Thank you! I agree - the iterator text should be clarified. I’ve added this to the Beta-2 list.

Where Next?

Popular Pragmatic Bookshelf topics Top

Mmm
Hi, build fails on: bracket-lib = “~0.8.1” when running on Mac Mini M1 Rust version 1.5.0: Compiling winit v0.22.2 error[E0308]: mi...
New
raul
Page 28: It implements io.ReaderAt on the store type. Sorry if it’s a dumb question but was the io.ReaderAt supposed to be io.ReadAt? ...
New
HarryDeveloper
Hi @venkats, It has been mentioned in the description of ‘Supervisory Job’ title that 2 things as mentioned below result in the same eff...
New
rmurray10127
Title: Intuitive Python: docker run… denied error (page 2) Attempted to run the docker command in both CLI and Powershell PS C:\Users\r...
New
New
brian-m-ops
#book-python-testing-with-pytest-second-edition Hi. Thanks for writing the book. I am just learning so this might just of been an issue ...
New
Henrai
Hi, I’m working on the Chapter 8 of the book. After I add add the point_offset, I’m still able to see acne: In the image above, I re...
New
a.zampa
@mfazio23 I’m following the indications of the book and arriver ad chapter 10, but the app cannot be compiled due to an error in the Bas...
New
New
SlowburnAZ
Getting an error when installing the dependencies at the start of this chapter: could not compile dependency :exla, "mix compile" failed...
New

Other popular topics Top

Devtalk
Hello Devtalk World! Please let us know a little about who you are and where you’re from :nerd_face:
New
New
AstonJ
Or looking forward to? :nerd_face:
498 13895 271
New
brentjanderson
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
New
Exadra37
Oh just spent so much time on this to discover now that RancherOS is in end of life but Rancher is refusing to mark the Github repo as su...
New
PragmaticBookshelf
Create efficient, elegant software tests in pytest, Python's most powerful testing framework. Brian Okken @brianokken Edited by Kat...
New
AstonJ
Saw this on TikTok of all places! :lol: Anyone heard of them before? Lite:
New
PragmaticBookshelf
Rails 7 completely redefines what it means to produce fantastic user experiences and provides a way to achieve all the benefits of single...
New
DevotionGeo
I have always used antique keyboards like Cherry MX 1800 or Cherry MX 8100 and almost always have modified the switches in some way, like...
New
PragmaticBookshelf
Explore the power of Ash Framework by modeling and building the domain for a real-world web application. Rebecca Le @sevenseacat and ...
New

Sub Categories: