Link plugins guide from elsewhere

1 files changed, 7 insertions, 0 deletions

diff --git a/src/doc/guide-macros.md b/src/doc/guide-macros.md
index 50b2c281fcf..c2c374d3e1f 100644
--- a/src/doc/guide-macros.md
+++ b/src/doc/guide-macros.md
@@ -526,3 +526,10 @@ tricky. Invoking the `log_syntax!` macro can help elucidate intermediate
 states, invoking `trace_macros!(true)` will automatically print those
 intermediate states out, and passing the flag `--pretty expanded` as a
 command-line argument to the compiler will show the result of expansion.
+
+If Rust's macro system can't do what you need, you may want to write a
+[compiler plugin](guide-plugin.html) instead. Compared to `macro_rules!`
+macros, this is significantly more work, the interfaces are much less stable,
+and the warnings about debugging apply ten-fold. In exchange you get the
+flexibility of running arbitrary Rust code within the compiler. Syntax
+extension plugins are sometimes called "procedural macros" for this reason.