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diff --git a/src/content/chapter5_advanced_features/lesson04_externals/en.html b/src/content/chapter5_advanced_features/lesson04_externals/en.html deleted file mode 100644 index 8815fa7..0000000 --- a/src/content/chapter5_advanced_features/lesson04_externals/en.html +++ /dev/null @@ -1,25 +0,0 @@ -<p> - Sometimes in our projects we want to use code written in other languages, most - commonly Erlang and JavaScript, depending on which runtime is being used. - Gleam's <em>external functions</em> and <em>external types</em> allow us to - import and use this non-Gleam code. -</p> -<p> - An external type is one that has no constructors. Gleam doesn't know what - shape it has or how to create one, it only knows that it exists. -</p> -<p> - An external function is one that has the <code>@external</code> attribute on - it, directing the compiler to use the specified module function as the - implementation, instead of Gleam code. -</p> -<p> - The compiler can't tell the types of functions written in other languages, so - when the external attribute is given type annotations must be provided. Gleam - trusts that the type given is correct so an inaccurate type annotation can - result in unexpected behaviour and crashes at runtime. Be careful! -</p> -<p> - External functions are useful but should be used sparingly. Prefer to write - Gleam code where possible. -</p> |