From 8a78e7e174e4e1dc42fcefc6b01f9d9e3fbfb356 Mon Sep 17 00:00:00 2001 From: A Thousand Ships <96648715+AThousandShips@users.noreply.github.com> Date: Sun, 17 Mar 2024 14:38:36 +0100 Subject: [PATCH] [Doc] Clarify behavior of `String.format` with keys in replacements --- doc/classes/String.xml | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/doc/classes/String.xml b/doc/classes/String.xml index 17f953f48ff..7fdd271d80e 100644 --- a/doc/classes/String.xml +++ b/doc/classes/String.xml @@ -239,6 +239,13 @@ print("User {id} is {name}.".format([["id", 42], ["name", "Godot"]])) [/codeblock] See also the [url=$DOCS_URL/tutorials/scripting/gdscript/gdscript_format_string.html]GDScript format string[/url] tutorial. + [b]Note:[/b] The replacement of placeholders is not done all at once, instead each placeholder is replaced in the order they are passed, this means that if one of the replacement strings contains a key it will also be replaced. This can be very powerful, but can also cause unexpected results if you are not careful. If you do not need to perform replacement in the replacement strings, make sure your replacements do not contain placeholders to ensure reliable results. + [codeblock] + print("{0} {1}".format(["{1}", "x"])) # Prints "x x". + print("{0} {1}".format(["x", "{0}"])) # Prints "x {0}". + print("{foo} {bar}".format({"foo": "{bar}", "bar": "baz"})) # Prints "baz baz". + print("{foo} {bar}".format({"bar": "baz", "foo": "{bar}"})) # Prints "{bar} baz". + [/codeblock] [b]Note:[/b] In C#, it's recommended to [url=https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/tokens/interpolated]interpolate strings with "$"[/url], instead.