(stdlib) Use more predictable format in float and double conversi…

…on to string
perlang-org · Oct 30, 2023 · 6b3e6d0 · 6b3e6d0
1 parent 50b1ff9
commit 6b3e6d0
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diff --git a/release-notes/v0.4.0.md b/release-notes/v0.4.0.md
@@ -12,6 +12,7 @@
 #### Data types
 - Implement `AsciiString` for ASCII-only strings [[#377][377]]
 - Implement `Utf8String` for strings with non-ASCII content [[#385][385]]
+- Use more predictable format in `float` and `double` conversion to string [[#414][414]]
 
 #### General
 - Enable nullability checks for the `Program` class [[#386][386]]
@@ -41,3 +42,4 @@
 [410]: https://github.com/perlang-org/perlang/pull/410
 [412]: https://github.com/perlang-org/perlang/pull/412
 [413]: https://github.com/perlang-org/perlang/pull/413
+[414]: https://github.com/perlang-org/perlang/pull/414
diff --git a/src/Perlang.Stdlib/Internal/Utils.cs b/src/Perlang.Stdlib/Internal/Utils.cs
@@ -27,6 +27,16 @@ public static String Stringify(object @object)
             {
                 return String.from(clrString);
             }
+            else if (@object is float f)
+            {
+                // Us an explicit format, so we can produce something equal in the C# and C++/fmt-based implementations
+                return String.from(f.ToString("G7", CultureInfo.InvariantCulture));
+            }
+            else if (@object is double d)
+            {
+                // Us an explicit format, so we can produce something equal in the C# and C++/fmt-based implementations
+                return String.from(d.ToString("G15", CultureInfo.InvariantCulture));
+            }
             else if (@object is IConvertible convertible)
             {
                 // The explicit IFormatProvider is required to ensure we use 123.45 format, regardless of