Functions

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diff --git a/lessons/src/lesson016_function_captures/code.gleam b/lessons/src/lesson016_function_captures/code.gleam
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+++ b/lessons/src/lesson016_function_captures/code.gleam
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+import gleam/io
+
+pub fn main() {
+  // These two statements are equivalent
+  let add_one_v1 = fn(x) { add(1, x) }
+  let add_one_v2 = add(1, _)
+
+  io.debug(add_one_v1(10))
+  io.debug(add_one_v2(10))
+}
+
+fn add(a: Int, b: Int) -> Int {
+  a + b
+}
diff --git a/lessons/src/lesson016_function_captures/text.html b/lessons/src/lesson016_function_captures/text.html
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+<p>
+  Gleam has a shorthand syntax for creating anonymous functions that take one
+  argument and immediately call another function with that argument: the
+  function capture syntax.
+</p>
+<p>
+  The anonymous function <code>fn(a) { some_function(..., a, ...) }</code> can
+  be written as <code>some_function(..., _, ...)</code>, with any number of
+  other arguments passed to the inner function. The underscore <code>_</code> is
+  a placeholder for the final argument.
+</p>