From 85155bb2b4b30870eee583a6bf635c6f521dd5cc Mon Sep 17 00:00:00 2001
From: Calvin Rose <calsrose@gmail.com>
Date: Sat, 23 Jan 2021 13:54:02 -0600
Subject: [PATCH] Reference #478 Update peg/compile to use dyn for default
 grammar.

---
 CHANGELOG.md        |  2 ++
 src/boot/boot.janet |  4 +++-
 src/core/ev.c       |  1 -
 src/core/peg.c      | 11 +++++++++--
 4 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ff23c354..70434837 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 All notable changes to this project will be documented in this file.
 
 ## ??? - Unreleased
+- Use `(dyn :peg-grammar)` for passing a default grammar to `peg/compile` instead of loading
+  `default-peg-grammar` directly from the root environment.
 - Add `ev/thread` for combining threading with the event loop.
 - Add `ev/do-thread` to make `ev/thread` easier to use.
 - Automatically set supervisor channel in `net/accept-loop` and `net/server` correctly.
diff --git a/src/boot/boot.janet b/src/boot/boot.janet
index 13c1daa0..9ad70396 100644
--- a/src/boot/boot.janet
+++ b/src/boot/boot.janet
@@ -2007,7 +2007,7 @@
      :a (range "az" "AZ")
      :s (set " \t\r\n\0\f\v")
      :w (range "az" "AZ" "09")
-     :h (range "09" "af")
+     :h (range "09" "af" "AF")
      :S (if-not :s 1)
      :W (if-not :w 1)
      :A (if-not :a 1)
@@ -2024,6 +2024,8 @@
      :s* (any :s)
      :h* (any :h)})
 
+(setdyn :peg-grammar default-peg-grammar)
+
 ###
 ###
 ### Evaluation and Compilation
diff --git a/src/core/ev.c b/src/core/ev.c
index abdf22f1..5effda18 100644
--- a/src/core/ev.c
+++ b/src/core/ev.c
@@ -2056,7 +2056,6 @@ static JanetEVGenericMessage janet_go_thread_subr(JanetEVGenericMessage args) {
                                       JANET_MARSHAL_UNSAFE, NULL, &nextbytes);
         if (!janet_checktype(fiberv, JANET_FIBER)) janet_panic("expected fiber");
         JanetFiber *fiber = janet_unwrap_fiber(fiberv);
-        janet_gcroot(fiberv);
         janet_schedule(fiber, value);
         janet_loop();
         args.tag = JANET_EV_TCTAG_NIL;
diff --git a/src/core/peg.c b/src/core/peg.c
index c3628839..ba0f0a8a 100644
--- a/src/core/peg.c
+++ b/src/core/peg.c
@@ -1486,7 +1486,13 @@ static JanetPeg *make_peg(Builder *b) {
 static JanetPeg *compile_peg(Janet x) {
     Builder builder;
     builder.grammar = janet_table(0);
-    builder.default_grammar = janet_get_core_table("default-peg-grammar");
+    builder.default_grammar = NULL;
+    {
+        Janet default_grammarv = janet_dyn("peg-grammar");
+        if (janet_checktype(default_grammarv, JANET_TABLE)) {
+            builder.default_grammar = janet_unwrap_table(default_grammarv);
+        }
+    }
     builder.tags = janet_table(0);
     builder.constants = NULL;
     builder.bytecode = NULL;
@@ -1656,7 +1662,8 @@ static const JanetReg peg_cfuns[] = {
         "peg/compile", cfun_peg_compile,
         JDOC("(peg/compile peg)\n\n"
              "Compiles a peg source data structure into a <core/peg>. This will speed up matching "
-             "if the same peg will be used multiple times.")
+             "if the same peg will be used multiple times. Will also use `(dyn :peg-grammar)` to suppliment "
+             "the grammar of the peg for otherwise undefined peg keywords.")
     },
     {
         "peg/match", cfun_peg_match,