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Show possible and desired results in tricky cases manual section

pull/402/head
Wilfred Hughes 2022-10-09 23:48:21 +07:00
parent 308a9c842a
commit a40d93e26c
1 changed files with 27 additions and 7 deletions
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manual/src/tricky_cases.md
Unescape Escape View File

@ -15,6 +15,8 @@ x
(x)
```
Possible result: <code><span style="background-color: PaleGreen; color: #000">(x)</span></code>
Desired result: <code><span style="background-color: PaleGreen; color: #000">(</span>x<span style="background-color: PaleGreen; color: #000">)</span></code>
This is tricky because `x` has changed its depth in the tree, but `x`
@ -35,6 +37,8 @@ expressions.
[x]
```
Desired result: <code><span style="background-color: #fbbd98; color: #000">(</span>x<span style="background-color: #fbbd98; color: #000">)</span> <span style="background-color: PaleGreen; color: #000">[</span>x<span style="background-color: PaleGreen; color: #000">]</span></code>
As with the wrapping case, we want to highlight the delimiters rather
than the `x`.
@ -93,7 +97,7 @@ where a later pair of delimiters are chosen.
```
We want to highlight `[[foo]]` being moved inside the
parentheses. However, a naive syntax differ prefers consider a removal
parentheses. However, a naive syntax differ prefers to consider a removal
of `()` in the before and an addition of `()` in the after to be more
minimal diff.
@ -160,10 +164,23 @@ A B
C D
```
Ideally we'd prefer marking contiguous nodes as novel, so we highlight
`A B` rather than `B\nA`. From the perspective of a
longest-common-subsequence algorithm, these two choices are
equivalent.
Possible result:
<pre><code>A <span style="background-color: PaleGreen; color: #000">B</span>
<span style="background-color: PaleGreen; color: #000">A</span> B
C D
</code></pre>
Preferred result:
<pre><code>A B
<span style="background-color: PaleGreen; color: #000">A</span> <span style="background-color: PaleGreen; color: #000">B</span>
C D
</code></pre>
Ideally we'd prefer marking contiguous nodes as novel. From the
perspective of a longest-common-subsequence algorithm, these two
choices are equivalent.
## Sliders (Nested)
@ -175,8 +192,9 @@ old1(old2)
old1(new1(old2))
```
Should this be <code>old1(<span style="background-color: PaleGreen; color: #000">new1(</span>old2<span style="background-color: PaleGreen; color: #000">)</span>)</code> or
<code>old1<span style="background-color: PaleGreen; color: #000">(new1</span>(old2)<span style="background-color: PaleGreen; color: #000">)</span></code>?
Possible result: <code>old1<span style="background-color: PaleGreen; color: #000">(new1</span>(old2)<span style="background-color: PaleGreen; color: #000">)</span></code>
Desired result: <code>old1(<span style="background-color: PaleGreen; color: #000">new1(</span>old2<span style="background-color: PaleGreen; color: #000">)</span>)</code>
The correct answer depends on the language. Most languages want to
prefer the inner delimiter, whereas Lisps and JSON prefer the outer
@ -208,6 +226,8 @@ function foo(x) { return x + 1; }
function bar(y) { baz(y); }
```
Possible result: <code>function <span style="background-color: PaleGreen; color: #000">bar</span>(<span style="background-color: PaleGreen; color: #000">y</span>) { <span style="background-color: PaleGreen; color: #000">baz(y)</span>; }</code>
In this example, we've deleted a function and written a completely
different one. A tree-based diff could match up the `function` and the
outer delimiters, resulting in a confusing display showing lots of