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</pre><pre class="rust">
<span class="comment">// Copyright 2014-2016 bluss and ndarray developers.</span>
<span class="comment">//</span>
<span class="comment">// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or</span>
<span class="comment">// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license</span>
<span class="comment">// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your</span>
<span class="comment">// option. This file may not be copied, modified, or distributed</span>
<span class="comment">// except according to those terms.</span>
<span class="kw">use</span> {<span class="ident">Ix</span>, <span class="ident">Ixs</span>};
<span class="kw">use</span> <span class="ident">error</span>::{<span class="ident">from_kind</span>, <span class="ident">ErrorKind</span>, <span class="ident">ShapeError</span>};
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::dim</span>::<span class="kw-2">*</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::axis::Axis</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::conversion::IntoDimension</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::dimension_trait::Dimension</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::ndindex::NdIndex</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::remove_axis::RemoveAxis</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::axes</span>::{<span class="ident">axes_of</span>, <span class="ident">Axes</span>, <span class="ident">AxisDescription</span>};
<span class="kw">pub</span> <span class="kw">use</span> <span class="self">self</span><span class="ident">::dynindeximpl::IxDynImpl</span>;
<span class="attribute">#[<span class="ident">macro_use</span>]</span> <span class="kw">mod</span> <span class="ident">macros</span>;
<span class="kw">mod</span> <span class="ident">axis</span>;
<span class="kw">mod</span> <span class="ident">conversion</span>;
<span class="kw">pub</span> <span class="kw">mod</span> <span class="ident">dim</span>;
<span class="kw">mod</span> <span class="ident">dimension_trait</span>;
<span class="kw">mod</span> <span class="ident">dynindeximpl</span>;
<span class="kw">mod</span> <span class="ident">ndindex</span>;
<span class="kw">mod</span> <span class="ident">remove_axis</span>;
<span class="kw">mod</span> <span class="ident">axes</span>;
<span class="doccomment">/// Calculate offset from `Ix` stride converting sign properly</span>
<span class="attribute">#[<span class="ident">inline</span>(<span class="ident">always</span>)]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">stride_offset</span>(<span class="ident">n</span>: <span class="ident">Ix</span>, <span class="ident">stride</span>: <span class="ident">Ix</span>) <span class="op">-</span><span class="op">></span> <span class="ident">isize</span> {
(<span class="ident">n</span> <span class="kw">as</span> <span class="ident">isize</span>) <span class="op">*</span> ((<span class="ident">stride</span> <span class="kw">as</span> <span class="ident">Ixs</span>) <span class="kw">as</span> <span class="ident">isize</span>)
}
<span class="doccomment">/// Check whether the given `dim` and `stride` lead to overlapping indices</span>
<span class="doccomment">///</span>
<span class="doccomment">/// There is overlap if, when iterating through the dimensions in the order</span>
<span class="doccomment">/// of maximum variation, the current stride is inferior to the sum of all</span>
<span class="doccomment">/// preceding strides multiplied by their corresponding dimensions.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The current implementation assumes strides to be positive</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">dim_stride_overlap</span><span class="op"><</span><span class="ident">D</span>: <span class="ident">Dimension</span><span class="op">></span>(<span class="ident">dim</span>: <span class="kw-2">&</span><span class="ident">D</span>, <span class="ident">strides</span>: <span class="kw-2">&</span><span class="ident">D</span>) <span class="op">-</span><span class="op">></span> <span class="ident">bool</span> {
<span class="kw">let</span> <span class="ident">order</span> <span class="op">=</span> <span class="ident">strides</span>.<span class="ident">_fastest_varying_stride_order</span>();
<span class="kw">let</span> <span class="ident">dim</span> <span class="op">=</span> <span class="ident">dim</span>.<span class="ident">slice</span>();
<span class="kw">let</span> <span class="ident">strides</span> <span class="op">=</span> <span class="ident">strides</span>.<span class="ident">slice</span>();
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">prev_offset</span> <span class="op">=</span> <span class="number">1</span>;
<span class="kw">for</span> <span class="kw-2">&</span><span class="ident">index</span> <span class="kw">in</span> <span class="ident">order</span>.<span class="ident">slice</span>() {
<span class="kw">let</span> <span class="ident">d</span> <span class="op">=</span> <span class="ident">dim</span>[<span class="ident">index</span>];
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">strides</span>[<span class="ident">index</span>];
<span class="comment">// any stride is ok if dimension is 1</span>
<span class="kw">if</span> <span class="ident">d</span> <span class="op">!</span><span class="op">=</span> <span class="number">1</span> <span class="op">&&</span> (<span class="ident">s</span> <span class="kw">as</span> <span class="ident">isize</span>) <span class="op"><</span> <span class="ident">prev_offset</span> {
<span class="kw">return</span> <span class="bool-val">true</span>;
}
<span class="ident">prev_offset</span> <span class="op">=</span> <span class="ident">stride_offset</span>(<span class="ident">d</span>, <span class="ident">s</span>);
}
<span class="bool-val">false</span>
}
<span class="doccomment">/// Check whether the given dimension and strides are memory safe</span>
<span class="doccomment">/// to index the provided slice.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// To be safe, no stride may be negative, and the offset corresponding</span>
<span class="doccomment">/// to the last element of each dimension should be smaller than the length</span>
<span class="doccomment">/// of the slice. Also, the strides should not allow a same element to be</span>
<span class="doccomment">/// referenced by two different index.</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">can_index_slice</span><span class="op"><</span><span class="ident">A</span>, <span class="ident">D</span>: <span class="ident">Dimension</span><span class="op">></span>(<span class="ident">data</span>: <span class="kw-2">&</span>[<span class="ident">A</span>], <span class="ident">dim</span>: <span class="kw-2">&</span><span class="ident">D</span>, <span class="ident">strides</span>: <span class="kw-2">&</span><span class="ident">D</span>)
<span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span>(), <span class="ident">ShapeError</span><span class="op">></span>
{
<span class="comment">// check lengths of axes.</span>
<span class="kw">let</span> <span class="ident">len</span> <span class="op">=</span> <span class="kw">match</span> <span class="ident">dim</span>.<span class="ident">size_checked</span>() {
<span class="prelude-val">Some</span>(<span class="ident">l</span>) <span class="op">=</span><span class="op">></span> <span class="ident">l</span>,
<span class="prelude-val">None</span> <span class="op">=</span><span class="op">></span> <span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">from_kind</span>(<span class="ident">ErrorKind::OutOfBounds</span>)),
};
<span class="comment">// check if strides are strictly positive (zero ok for len 0)</span>
<span class="kw">for</span> <span class="kw-2">&</span><span class="ident">s</span> <span class="kw">in</span> <span class="ident">strides</span>.<span class="ident">slice</span>() {
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">s</span> <span class="kw">as</span> <span class="ident">Ixs</span>;
<span class="kw">if</span> <span class="ident">s</span> <span class="op"><</span> <span class="number">1</span> <span class="op">&&</span> (<span class="ident">len</span> <span class="op">!</span><span class="op">=</span> <span class="number">0</span> <span class="op">|</span><span class="op">|</span> <span class="ident">s</span> <span class="op"><</span> <span class="number">0</span>) {
<span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">from_kind</span>(<span class="ident">ErrorKind::Unsupported</span>));
}
}
<span class="kw">if</span> <span class="ident">len</span> <span class="op">=</span><span class="op">=</span> <span class="number">0</span> {
<span class="kw">return</span> <span class="prelude-val">Ok</span>(());
}
<span class="comment">// check that the maximum index is in bounds</span>
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">last_index</span> <span class="op">=</span> <span class="ident">dim</span>.<span class="ident">clone</span>();
<span class="kw">for</span> <span class="ident">index</span> <span class="kw">in</span> <span class="ident">last_index</span>.<span class="ident">slice_mut</span>().<span class="ident">iter_mut</span>() {
<span class="kw-2">*</span><span class="ident">index</span> <span class="op">-</span><span class="op">=</span> <span class="number">1</span>;
}
<span class="kw">if</span> <span class="kw">let</span> <span class="prelude-val">Some</span>(<span class="ident">offset</span>) <span class="op">=</span> <span class="ident">stride_offset_checked_arithmetic</span>(<span class="ident">dim</span>,
<span class="ident">strides</span>,
<span class="kw-2">&</span><span class="ident">last_index</span>)
{
<span class="comment">// offset is guaranteed to be positive so no issue converting</span>
<span class="comment">// to usize here</span>
<span class="kw">if</span> (<span class="ident">offset</span> <span class="kw">as</span> <span class="ident">usize</span>) <span class="op">></span><span class="op">=</span> <span class="ident">data</span>.<span class="ident">len</span>() {
<span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">from_kind</span>(<span class="ident">ErrorKind::OutOfBounds</span>));
}
<span class="kw">if</span> <span class="ident">dim_stride_overlap</span>(<span class="ident">dim</span>, <span class="ident">strides</span>) {
<span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">from_kind</span>(<span class="ident">ErrorKind::Unsupported</span>));
}
} <span class="kw">else</span> {
<span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">from_kind</span>(<span class="ident">ErrorKind::OutOfBounds</span>));
}
<span class="prelude-val">Ok</span>(())
}
<span class="doccomment">/// Return stride offset for this dimension and index.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Return None if the indices are out of bounds, or the calculation would wrap</span>
<span class="doccomment">/// around.</span>
<span class="kw">fn</span> <span class="ident">stride_offset_checked_arithmetic</span><span class="op"><</span><span class="ident">D</span><span class="op">></span>(<span class="ident">dim</span>: <span class="kw-2">&</span><span class="ident">D</span>, <span class="ident">strides</span>: <span class="kw-2">&</span><span class="ident">D</span>, <span class="ident">index</span>: <span class="kw-2">&</span><span class="ident">D</span>)
<span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">isize</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">D</span>: <span class="ident">Dimension</span>
{
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">offset</span> <span class="op">=</span> <span class="number">0</span>;
<span class="kw">for</span> (<span class="kw-2">&</span><span class="ident">d</span>, <span class="kw-2">&</span><span class="ident">i</span>, <span class="kw-2">&</span><span class="ident">s</span>) <span class="kw">in</span> <span class="macro">izip!</span>(<span class="ident">dim</span>.<span class="ident">slice</span>(), <span class="ident">index</span>.<span class="ident">slice</span>(), <span class="ident">strides</span>.<span class="ident">slice</span>()) {
<span class="kw">if</span> <span class="ident">i</span> <span class="op">></span><span class="op">=</span> <span class="ident">d</span> {
<span class="kw">return</span> <span class="prelude-val">None</span>;
}
<span class="kw">if</span> <span class="kw">let</span> <span class="prelude-val">Some</span>(<span class="ident">offset_</span>) <span class="op">=</span> (<span class="ident">i</span> <span class="kw">as</span> <span class="ident">isize</span>)
.<span class="ident">checked_mul</span>((<span class="ident">s</span> <span class="kw">as</span> <span class="ident">Ixs</span>) <span class="kw">as</span> <span class="ident">isize</span>)
.<span class="ident">and_then</span>(<span class="op">|</span><span class="ident">x</span><span class="op">|</span> <span class="ident">x</span>.<span class="ident">checked_add</span>(<span class="ident">offset</span>)) {
<span class="ident">offset</span> <span class="op">=</span> <span class="ident">offset_</span>;
} <span class="kw">else</span> {
<span class="kw">return</span> <span class="prelude-val">None</span>;
}
}
<span class="prelude-val">Some</span>(<span class="ident">offset</span>)
}
<span class="doccomment">/// Stride offset checked general version (slices)</span>
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">stride_offset_checked</span>(<span class="ident">dim</span>: <span class="kw-2">&</span>[<span class="ident">Ix</span>], <span class="ident">strides</span>: <span class="kw-2">&</span>[<span class="ident">Ix</span>], <span class="ident">index</span>: <span class="kw-2">&</span>[<span class="ident">Ix</span>]) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">isize</span><span class="op">></span> {
<span class="kw">if</span> <span class="ident">index</span>.<span class="ident">len</span>() <span class="op">!</span><span class="op">=</span> <span class="ident">dim</span>.<span class="ident">len</span>() {
<span class="kw">return</span> <span class="prelude-val">None</span>;
}
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">offset</span> <span class="op">=</span> <span class="number">0</span>;
<span class="kw">for</span> (<span class="kw-2">&</span><span class="ident">d</span>, <span class="kw-2">&</span><span class="ident">i</span>, <span class="kw-2">&</span><span class="ident">s</span>) <span class="kw">in</span> <span class="macro">izip!</span>(<span class="ident">dim</span>, <span class="ident">index</span>, <span class="ident">strides</span>) {
<span class="kw">if</span> <span class="ident">i</span> <span class="op">></span><span class="op">=</span> <span class="ident">d</span> {
<span class="kw">return</span> <span class="prelude-val">None</span>;
}
<span class="ident">offset</span> <span class="op">+</span><span class="op">=</span> <span class="ident">stride_offset</span>(<span class="ident">i</span>, <span class="ident">s</span>);
}
<span class="prelude-val">Some</span>(<span class="ident">offset</span>)
}
<span class="doccomment">/// Implementation-specific extensions to `Dimension`</span>
<span class="kw">pub</span> <span class="kw">trait</span> <span class="ident">DimensionExt</span> {
<span class="comment">// note: many extensions go in the main trait if they need to be special-</span>
<span class="comment">// cased per dimension</span>
<span class="doccomment">/// Get the dimension at `axis`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *Panics* if `axis` is out of bounds.</span>
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">axis</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">axis</span>: <span class="ident">Axis</span>) <span class="op">-</span><span class="op">></span> <span class="ident">Ix</span>;
<span class="doccomment">/// Set the dimension at `axis`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *Panics* if `axis` is out of bounds.</span>
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">set_axis</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">axis</span>: <span class="ident">Axis</span>, <span class="ident">value</span>: <span class="ident">Ix</span>);
}
<span class="kw">impl</span><span class="op"><</span><span class="ident">D</span><span class="op">></span> <span class="ident">DimensionExt</span> <span class="kw">for</span> <span class="ident">D</span>
<span class="kw">where</span> <span class="ident">D</span>: <span class="ident">Dimension</span>
{
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">axis</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">axis</span>: <span class="ident">Axis</span>) <span class="op">-</span><span class="op">></span> <span class="ident">Ix</span> {
<span class="self">self</span>[<span class="ident">axis</span>.<span class="ident">index</span>()]
}
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">set_axis</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">axis</span>: <span class="ident">Axis</span>, <span class="ident">value</span>: <span class="ident">Ix</span>) {
<span class="self">self</span>[<span class="ident">axis</span>.<span class="ident">index</span>()] <span class="op">=</span> <span class="ident">value</span>;
}
}
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span><span class="op">></span> <span class="ident">DimensionExt</span> <span class="kw">for</span> [<span class="ident">Ix</span>]
{
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">axis</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">axis</span>: <span class="ident">Axis</span>) <span class="op">-</span><span class="op">></span> <span class="ident">Ix</span> {
<span class="self">self</span>[<span class="ident">axis</span>.<span class="ident">index</span>()]
}
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">set_axis</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">axis</span>: <span class="ident">Axis</span>, <span class="ident">value</span>: <span class="ident">Ix</span>) {
<span class="self">self</span>[<span class="ident">axis</span>.<span class="ident">index</span>()] <span class="op">=</span> <span class="ident">value</span>;
}
}
<span class="doccomment">/// Collapse axis `axis` and shift so that only subarray `index` is</span>
<span class="doccomment">/// available.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// **Panics** if `index` is larger than the size of the axis</span>
<span class="comment">// FIXME: Move to Dimension trait</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">do_sub</span><span class="op"><</span><span class="ident">A</span>, <span class="ident">D</span>: <span class="ident">Dimension</span><span class="op">></span>(<span class="ident">dims</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">D</span>, <span class="ident">ptr</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">A</span>, <span class="ident">strides</span>: <span class="kw-2">&</span><span class="ident">D</span>,
<span class="ident">axis</span>: <span class="ident">usize</span>, <span class="ident">index</span>: <span class="ident">Ix</span>) {
<span class="kw">let</span> <span class="ident">dim</span> <span class="op">=</span> <span class="ident">dims</span>.<span class="ident">slice</span>()[<span class="ident">axis</span>];
<span class="kw">let</span> <span class="ident">stride</span> <span class="op">=</span> <span class="ident">strides</span>.<span class="ident">slice</span>()[<span class="ident">axis</span>];
<span class="macro">ndassert!</span>(<span class="ident">index</span> <span class="op"><</span> <span class="ident">dim</span>,
<span class="macro">concat!</span>(<span class="string">"subview: Index {} must be less than axis length {} "</span>,
<span class="string">"for array with shape {:?}"</span>),
<span class="ident">index</span>, <span class="ident">dim</span>, <span class="kw-2">*</span><span class="ident">dims</span>);
<span class="ident">dims</span>.<span class="ident">slice_mut</span>()[<span class="ident">axis</span>] <span class="op">=</span> <span class="number">1</span>;
<span class="kw">let</span> <span class="ident">off</span> <span class="op">=</span> <span class="ident">stride_offset</span>(<span class="ident">index</span>, <span class="ident">stride</span>);
<span class="kw">unsafe</span> {
<span class="kw-2">*</span><span class="ident">ptr</span> <span class="op">=</span> <span class="ident">ptr</span>.<span class="ident">offset</span>(<span class="ident">off</span>);
}
}
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">merge_axes</span><span class="op"><</span><span class="ident">D</span><span class="op">></span>(<span class="ident">dim</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">D</span>, <span class="ident">strides</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">D</span>, <span class="ident">take</span>: <span class="ident">Axis</span>, <span class="ident">into</span>: <span class="ident">Axis</span>) <span class="op">-</span><span class="op">></span> <span class="ident">bool</span>
<span class="kw">where</span> <span class="ident">D</span>: <span class="ident">Dimension</span>,
{
<span class="kw">let</span> <span class="ident">il</span> <span class="op">=</span> <span class="ident">dim</span>.<span class="ident">axis</span>(<span class="ident">into</span>);
<span class="kw">let</span> <span class="ident">is</span> <span class="op">=</span> <span class="ident">strides</span>.<span class="ident">axis</span>(<span class="ident">into</span>) <span class="kw">as</span> <span class="ident">Ixs</span>;
<span class="kw">let</span> <span class="ident">tl</span> <span class="op">=</span> <span class="ident">dim</span>.<span class="ident">axis</span>(<span class="ident">take</span>);
<span class="kw">let</span> <span class="ident">ts</span> <span class="op">=</span> <span class="ident">strides</span>.<span class="ident">axis</span>(<span class="ident">take</span>) <span class="kw">as</span> <span class="ident">Ixs</span>;
<span class="kw">if</span> <span class="ident">il</span> <span class="kw">as</span> <span class="ident">Ixs</span> <span class="op">*</span> <span class="ident">is</span> <span class="op">!</span><span class="op">=</span> <span class="ident">ts</span> {
<span class="kw">return</span> <span class="bool-val">false</span>;
}
<span class="comment">// merge them</span>
<span class="ident">dim</span>.<span class="ident">set_axis</span>(<span class="ident">into</span>, <span class="ident">il</span> <span class="op">*</span> <span class="ident">tl</span>);
<span class="ident">dim</span>.<span class="ident">set_axis</span>(<span class="ident">take</span>, <span class="number">1</span>);
<span class="bool-val">true</span>
}
<span class="comment">// NOTE: These tests are not compiled & tested</span>
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">test</span>)]</span>
<span class="kw">mod</span> <span class="ident">test</span> {
<span class="kw">use</span> <span class="kw">super</span><span class="ident">::IntoDimension</span>;
<span class="kw">use</span> <span class="ident">error</span>::{<span class="ident">from_kind</span>, <span class="ident">ErrorKind</span>};
<span class="attribute">#[<span class="ident">test</span>]</span>
<span class="kw">fn</span> <span class="ident">slice_indexing_uncommon_strides</span>() {
<span class="kw">let</span> <span class="ident">v</span>: <span class="ident">Vec</span><span class="op"><</span><span class="kw">_</span><span class="op">></span> <span class="op">=</span> (<span class="number">0</span>..<span class="number">12</span>).<span class="ident">collect</span>();
<span class="kw">let</span> <span class="ident">dim</span> <span class="op">=</span> (<span class="number">2</span>, <span class="number">3</span>, <span class="number">2</span>).<span class="ident">into_dimension</span>();
<span class="kw">let</span> <span class="ident">strides</span> <span class="op">=</span> (<span class="number">1</span>, <span class="number">2</span>, <span class="number">6</span>).<span class="ident">into_dimension</span>();
<span class="macro">assert!</span>(<span class="kw">super</span><span class="ident">::can_index_slice</span>(<span class="kw-2">&</span><span class="ident">v</span>, <span class="kw-2">&</span><span class="ident">dim</span>, <span class="kw-2">&</span><span class="ident">strides</span>).<span class="ident">is_ok</span>());
<span class="kw">let</span> <span class="ident">strides</span> <span class="op">=</span> (<span class="number">2</span>, <span class="number">4</span>, <span class="number">12</span>).<span class="ident">into_dimension</span>();
<span class="macro">assert_eq!</span>(<span class="kw">super</span><span class="ident">::can_index_slice</span>(<span class="kw-2">&</span><span class="ident">v</span>, <span class="kw-2">&</span><span class="ident">dim</span>, <span class="kw-2">&</span><span class="ident">strides</span>),
<span class="prelude-val">Err</span>(<span class="ident">from_kind</span>(<span class="ident">ErrorKind::OutOfBounds</span>)));
}
<span class="attribute">#[<span class="ident">test</span>]</span>
<span class="kw">fn</span> <span class="ident">overlapping_strides_dim</span>() {
<span class="kw">let</span> <span class="ident">dim</span> <span class="op">=</span> (<span class="number">2</span>, <span class="number">3</span>, <span class="number">2</span>).<span class="ident">into_dimension</span>();
<span class="kw">let</span> <span class="ident">strides</span> <span class="op">=</span> (<span class="number">5</span>, <span class="number">2</span>, <span class="number">1</span>).<span class="ident">into_dimension</span>();
<span class="macro">assert!</span>(<span class="kw">super</span><span class="ident">::dim_stride_overlap</span>(<span class="kw-2">&</span><span class="ident">dim</span>, <span class="kw-2">&</span><span class="ident">strides</span>));
<span class="kw">let</span> <span class="ident">strides</span> <span class="op">=</span> (<span class="number">6</span>, <span class="number">2</span>, <span class="number">1</span>).<span class="ident">into_dimension</span>();
<span class="macro">assert!</span>(<span class="op">!</span><span class="kw">super</span><span class="ident">::dim_stride_overlap</span>(<span class="kw-2">&</span><span class="ident">dim</span>, <span class="kw-2">&</span><span class="ident">strides</span>));
<span class="kw">let</span> <span class="ident">strides</span> <span class="op">=</span> (<span class="number">6</span>, <span class="number">0</span>, <span class="number">1</span>).<span class="ident">into_dimension</span>();
<span class="macro">assert!</span>(<span class="kw">super</span><span class="ident">::dim_stride_overlap</span>(<span class="kw-2">&</span><span class="ident">dim</span>, <span class="kw-2">&</span><span class="ident">strides</span>));
}
}
</pre></div>
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