feat(corelib): Option iterator

[cairolover]

Adds IntoIter and Iterator implementations for Option<T>

[reviewable-StarkWare]

This change is 

[orizi]

Reviewed all commit messages.
Reviewable status: 0 of 2 files reviewed, 3 unresolved discussions (waiting on @cairolover)

---

corelib/src/test/option_test.cairo line 146 at r1 (raw file):

    let x: Option<u32> = Option::Some(5);
    let mut x_iter = x.into_iter();
    assert!(x_iter.next() == Option::Some(5));

Suggestion:

    assert!(x_iter.next() == Option::Some(5));
    assert!(x_iter.next() == Option::None);

---

corelib/src/option.cairo line 479 at r1 (raw file):

    fn next(ref self: OptionIter<T>) -> Option<T> {
        self.inner
    }

Suggestion:

impl OptionIterator<T> of Iterator<OptionIter<T>> {
    type Item = T;
    fn next(ref self: OptionIter<T>) -> Option<T> {
        let item = self.inner;
        self.inner = Option::None;
        item
    }

---

corelib/src/option.cairo line 489 at r1 (raw file):

        OptionIter { inner: self }
    }
}

Suggestion:

impl OptionIntoIterator<T> of IntoIterator<Option<T>> {
    type IntoIter = OptionIter<T>;

    #[inline]
    fn into_iter(self: Option<T>) -> OptionIter<T> {
        OptionIter { inner: self }
    }
}

[cairolover]

Reviewable status: 0 of 2 files reviewed, 3 unresolved discussions (waiting on @orizi)

---

corelib/src/test/option_test.cairo line 146 at r1 (raw file):

    let x: Option<u32> = Option::Some(5);
    let mut x_iter = x.into_iter();
    assert!(x_iter.next() == Option::Some(5));

Done.

---

corelib/src/option.cairo line 479 at r1 (raw file):

    fn next(ref self: OptionIter<T>) -> Option<T> {
        self.inner
    }

Done.

---

corelib/src/option.cairo line 489 at r1 (raw file):

        OptionIter { inner: self }
    }
}

Done.

[orizi]

Reviewed 2 of 2 files at r2, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @cairolover)

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corelib/src/option.cairo line 147 at r2 (raw file):

//! [`into_iter`]: IntoIterator::into_iter

use crate::iter::{IntoIterator, Iterator};

probably remove the import itself - for the time being - in general until we break version 2023_01 where visibility modifiers will be ignored, we attempt to reduce the number of uses - as they add an actual viewable item in that case. (and here you use these still only once)

Code quote:

use crate::iter::{IntoIterator, Iterator};

[cairolover]

Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion (waiting on @orizi)

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corelib/src/option.cairo line 147 at r2 (raw file):

Previously, orizi wrote…

probably remove the import itself - for the time being - in general until we break version 2023_01 where visibility modifiers will be ignored, we attempt to reduce the number of uses - as they add an actual viewable item in that case. (and here you use these still only once)

Done.

[cairolover]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @orizi)

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corelib/src/option.cairo line 147 at r2 (raw file):

Previously, cairolover (cairolover) wrote…

Done.

by the way - shouldn't iterator traits be part of the prelude?

[orizi]

Reviewed 2 of 2 files at r3, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @cairolover)

---

corelib/src/option.cairo line 147 at r2 (raw file):

Previously, cairolover (cairolover) wrote…

by the way - shouldn't iterator traits be part of the prelude?

quite possibly it would make more sense.

---

a discussion (no related file):
@enitrat for 2nd eye doc.

[enitrat]

Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @cairolover)

[orizi]

Reviewed 1 of 2 files at r4, all commit messages.
Reviewable status: 1 of 2 files reviewed, 2 unresolved discussions (waiting on @cairolover)

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corelib/src/test/option_test.cairo line 1 at r4 (raw file):

use crate::iter::{IntoIterator, Iterator};

i believe shouldn't be required after rebase.

Code quote:

use crate::iter::{IntoIterator, Iterator};

[cairolover]

Reviewable status: 1 of 2 files reviewed, 2 unresolved discussions (waiting on @orizi)

---

corelib/src/test/option_test.cairo line 1 at r4 (raw file):

Previously, orizi wrote…

i believe shouldn't be required after rebase.

The other one has not been merged yet. I'll revisit once it is

[orizi]

Reviewable status: 1 of 2 files reviewed, all discussions resolved (waiting on @cairolover)

---

a discussion (no related file):
@gilbens-starkware for 2nd eye.

[gilbens-starkware]

Reviewable status: 1 of 2 files reviewed, all discussions resolved (waiting on @orizi)