Merge pull request #1230 from mark-i-m/i128

Add 128-bit ints to ch3
rust-lang · Mar 21, 2018 · d77c067 · d77c067
2 parents d2ee2fc + ce3eb47
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diff --git a/second-edition/dictionary.txt b/second-edition/dictionary.txt
@@ -75,6 +75,7 @@ CPUs
 cratesio
 CRLF
 cryptocurrencies
+cryptographic
 cryptographically
 CStr
 CString
@@ -227,6 +228,7 @@ libreoffice
 libstd
 lifecycle
 LimitTracker
+LLVM
 lobally
 locators
 LockResult
@@ -272,6 +274,7 @@ namespace
 namespaced
 namespaces
 namespacing
+natively
 newfound
 NewJob
 NewsArticle

diff --git a/second-edition/src/appendix-06-newest-features.md b/second-edition/src/appendix-06-newest-features.md
@@ -112,3 +112,18 @@ fn main() {
 
 The `...` syntax is still accepted in matches, but it is not accepted in
 expressions. `..=` should be preferred.
+
+## 128-bit integers
+
+Rust 1.26.0 added 128-bit integer primitives:
+
+- `u128`: A 128-bit unsigned integer with range [0, 2^128 - 1]
+- `i128`: A 128-bit signed integer with range [-(2^127), 2^127 - 1]
+
+These primitive are implemented efficiently via LLVM support. They
+are available even on platforms that don't natively support 128-bit
+integers and can be used like the other integer types.
+
+These primitives can be very useful for algorithms that need to use
+very large integers efficiently, such as certain cryptographic
+algorithms.