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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:03:36 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:03:36 +0000
commit17d40c6057c88f4c432b0d7bac88e1b84cb7e67f (patch)
tree3f66c4a5918660bb8a758ab6cda5ff8ee4f6cdcd /src/tools/clippy/src/docs/comparison_to_empty.txt
parentAdding upstream version 1.64.0+dfsg1. (diff)
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Adding upstream version 1.65.0+dfsg1.upstream/1.65.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+### What it does
+Checks for comparing to an empty slice such as `""` or `[]`,
+and suggests using `.is_empty()` where applicable.
+
+### Why is this bad?
+Some structures can answer `.is_empty()` much faster
+than checking for equality. So it is good to get into the habit of using
+`.is_empty()`, and having it is cheap.
+Besides, it makes the intent clearer than a manual comparison in some contexts.
+
+### Example
+
+```
+if s == "" {
+ ..
+}
+
+if arr == [] {
+ ..
+}
+```
+Use instead:
+```
+if s.is_empty() {
+ ..
+}
+
+if arr.is_empty() {
+ ..
+}
+``` \ No newline at end of file