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Switch out item for byte to avoid overloading byte

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Carol (Nichols || Goulding) 2016-08-02 17:07:34 -04:00
parent 8e5bba01d6
commit d61336d619
1 changed files with 12 additions and 13 deletions
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25
src/ch04-03-slices.md
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@ -24,8 +24,8 @@ the word, though. Let’s try that:
fn first_word(s: &String) -> usize {
let bytes = s.as_bytes();
for (i, &byte) in bytes.iter().enumerate() {
if byte == 32 {
for (i, &item) in bytes.iter().enumerate() {
if item == 32 {
return i;
}
}
@ -45,7 +45,7 @@ check if a value is a space, we will convert our String to an
array of bytes using the `.as_bytes()` method.
```rust,ignore
for (i, &byte) in bytes.iter().enumerate() {
for (i, &item) in bytes.iter().enumerate() {
```
We will be discussing iterators in more detail in Chapter XX, but for
@ -56,12 +56,11 @@ second element is a reference to the element itself. This is a bit
nicer than calculating the index ourselves.
Since it’s a tuple, we can use patterns, just like elsewhere in Rust. So we
match against the tuple with i for the index and &byte for the byte itself.
Since we get a reference to a byte, we can put the `&` in the pattern, and then
the binding `byte` will hold the actual byte, not a reference to a byte.
match against the tuple with i for the index and &item for a single byte. Since
we get a reference from `.iter().enumerate()`, we use `&` in the pattern.
```rust,ignore
if byte == 32 {
if item == 32 {
return i;
}
}
@ -81,8 +80,8 @@ that it will still be valid in the future. Consider this:
# fn first_word(s: &String) -> usize {
# let bytes = s.as_bytes();
#
# for (i, &byte) in bytes.iter().enumerate() {
# if byte == 32 {
# for (i, &item) in bytes.iter().enumerate() {
# if item == 32 {
# return i;
# }
# }
@ -181,8 +180,8 @@ With this in mind, let’s re-write `first_word()` to return a slice:
fn first_word(s: &String) -> &str {
let bytes = s.as_bytes();
for (i, &byte) in bytes.iter().enumerate() {
if byte == 32 {
for (i, &item) in bytes.iter().enumerate() {
if item == 32 {
return &s[0..i];
}
}
@ -279,8 +278,8 @@ with no loss of functionality:
# fn first_word(s: &str) -> &str {
# let bytes = s.as_bytes();
#
# for (i, &byte) in bytes.iter().enumerate() {
# if byte == 32 {
# for (i, &item) in bytes.iter().enumerate() {
# if item == 32 {
# return &s[0..i];
# }
# }