Export of internal Abseil changes

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b984c7c1cbee4253192c833046bfcfa16dca8ccf by Dino Radakovic <dinor@google.com>:

Restrict visibility of absl/flags:commandlineflag_internal

PiperOrigin-RevId: 438591894
Change-Id: I12a6392b2c7f9f1263c741dfd6c43ae22e903aad

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81315601aab70bb6ac2d17655a727d7f9ee2ff95 by Justin Lebar <jlebar@google.com>:

Update example in str_join.h to use a lambda.

PiperOrigin-RevId: 438390035
Change-Id: Icc707b972e5a369a71ad774004fdf0a17a9b33a7

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1c3c7921224e505faca8617b073f657d3737219f by Dino Radakovic <dinor@google.com>:

Internal change

PiperOrigin-RevId: 438386036
Change-Id: I6066da1b5a1ddf5af265944a31ed298297b4f2e1

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2d6885f78481f04e0e7ee86060aec15b677144f3 by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 438378389
Change-Id: If70dd9114114eb44e85afccd521e7fb7e1436b88

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7f8282ddee7fcd032e01cbfe65c11c2d166cceb8 by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 438374554
Change-Id: I993367952af1dc83bd5aa0ae19a64c024f457fdd

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ce65ba28f6031e45db8fa5118a05410f5166fd7a by Abseil Team <absl-team@google.com>:

Spelling gardening: Heterogeneous has an "e" after the "n".

PiperOrigin-RevId: 438374411
Change-Id: If1a9098a5d04338837998883739c7b555efa62b4
GitOrigin-RevId: b984c7c1cbee4253192c833046bfcfa16dca8ccf

1 files changed, 9 insertions, 15 deletions

diff --git a/absl/strings/str_join.h b/absl/strings/str_join.h
index 33534536..ee5ae7ef 100644
--- a/absl/strings/str_join.h
+++ b/absl/strings/str_join.h
@@ -72,21 +72,15 @@ ABSL_NAMESPACE_BEGIN
 // functions. You may provide your own Formatter to enable `absl::StrJoin()` to
 // work with arbitrary types.
 //
-// The following is an example of a custom Formatter that simply uses
-// `std::to_string()` to format an integer as a std::string.
-//
-//   struct MyFormatter {
-//     void operator()(std::string* out, int i) const {
-//       out->append(std::to_string(i));
-//     }
-//   };
-//
-// You would use the above formatter by passing an instance of it as the final
-// argument to `absl::StrJoin()`:
-//
-//   std::vector<int> v = {1, 2, 3, 4};
-//   std::string s = absl::StrJoin(v, "-", MyFormatter());
-//   EXPECT_EQ("1-2-3-4", s);
+// The following is an example of a custom Formatter that uses
+// `absl::FormatDuration` to join a list of `absl::Duration`s.
+//
+//   std::vector<absl::Duration> v = {absl::Seconds(1), absl::Milliseconds(10)};
+//   std::string s =
+//       absl::StrJoin(v, ", ", [](std::string* out, absl::Duration dur) {
+//         absl::StrAppend(out, absl::FormatDuration(dur));
+//       });
+//   EXPECT_EQ("1s, 10ms", s);
 //
 // The following standard formatters are provided within this file:
 //