Compiling generates unused variable warnings

[dashbitco]

Compiling generates unused variable warnings

[josevalim]

Released!

[sorentwo]

❤️ 💛 💚 💙 💜

[milmazz]

@josevalim I've been contributing to oban very recently, and I was struggling to find what was causing the unused variable warnings in the aforementioned cron parser until I found this issue. So, I tried with the current version on master and indeed it fixes the issue, thanks 👏

I was wondering if you have any plan to make a release soon since the latest one is from Dec 11, 2019.

[sorentwo]

Thanks for releasing those changes. I upgraded to 0.6.0 and compiled again but I'm still seeing the same errors. Here's a relevant section of the compilation output:

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:1059: Oban.Crontab.Parser.cron__149/6

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:1063: Oban.Crontab.Parser.cron__151/6

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:2082: Oban.Crontab.Parser.cron__301/6

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:2086: Oban.Crontab.Parser.cron__303/6

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:3105: Oban.Crontab.Parser.cron__453/6

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:3109: Oban.Crontab.Parser.cron__455/6

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:4314: Oban.Crontab.Parser.cron__619/6

warning: variable "user_acc" is unused (if the variable is not meant to be used, prefix it with an underscore)
  lib/oban/crontab/parser.ex:4318: Oban.Crontab.Parser.cron__621/6

Generated oban app
Generating lib/oban/crontab/parser.ex

And here is the diff in the file (sorry, I know it is huge).

diff --git a/lib/oban/crontab/parser.ex b/lib/oban/crontab/parser.ex
index c1c8686..5b7dd88 100644
--- a/lib/oban/crontab/parser.ex
+++ b/lib/oban/crontab/parser.ex
@@ -1,5 +1,5 @@
 # Generated from lib/oban/crontab/parser.ex.exs, do not edit.
-# Generated at 2020-05-23 07:07:21Z.
+# Generated at 2020-05-25 15:18:25Z.
 
 defmodule Oban.Crontab.Parser do
   @moduledoc false
@@ -55,7 +55,7 @@ defp cron__3(<<",", rest::binary>>, acc, stack, context, comb__line, comb__offse
 
   defp cron__3(rest, _acc, _stack, context, line, offset) do
     {:error,
-     "expected string \"*\" or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"/\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9 or string \"*\" or string \",\"",
+     "expected string \"*\" or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"/\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or string \"*\" or string \",\"",
      rest, context, line, offset}
   end
 
@@ -127,6 +127,8 @@ defp cron__15(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__16(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__17(
       rest,
       (
@@ -141,6 +143,8 @@ defp cron__16(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__17(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__18(
       rest,
       [
@@ -212,6 +216,8 @@ defp cron__26(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__27(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__28(
       rest,
       (
@@ -274,6 +280,8 @@ defp cron__34(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__35(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__36(
       rest,
       (
@@ -288,6 +296,7 @@ defp cron__35(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__36(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__37(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -351,6 +360,8 @@ defp cron__48(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__49(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__50(
       rest,
       (
@@ -413,6 +424,8 @@ defp cron__56(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__57(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__58(
       rest,
       (
@@ -427,6 +440,7 @@ defp cron__57(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__58(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__59(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -499,6 +513,8 @@ defp cron__68(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__69(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__70(
       rest,
       (
@@ -513,6 +529,7 @@ defp cron__69(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__70(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__71(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -605,6 +622,8 @@ defp cron__87(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__88(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__89(
       rest,
       (
@@ -619,6 +638,8 @@ defp cron__88(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__89(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__90(
       rest,
       [
@@ -690,6 +711,8 @@ defp cron__98(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__99(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__100(
       rest,
       (
@@ -752,6 +775,8 @@ defp cron__106(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__107(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__108(
       rest,
       (
@@ -766,6 +791,7 @@ defp cron__107(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__108(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__109(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -829,6 +855,8 @@ defp cron__120(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__121(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__122(
       rest,
       (
@@ -891,6 +919,8 @@ defp cron__128(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__129(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__130(
       rest,
       (
@@ -905,6 +935,7 @@ defp cron__129(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__130(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__131(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -977,6 +1008,8 @@ defp cron__140(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__141(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__142(
       rest,
       (
@@ -991,6 +1024,7 @@ defp cron__141(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__142(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__143(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -1023,6 +1057,7 @@ defp cron__74(
   end
 
   defp cron__144(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__145(rest, [minutes: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -1040,7 +1075,8 @@ defp cron__147(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, c
   end
 
   defp cron__147(rest, _acc, _stack, context, line, offset) do
-    {:error, "expected byte equal to ?  or equal to 9", rest, context, line, offset}
+    {:error, "expected ASCII character equal to ' ' or equal to '\\t'", rest, context, line,
+     offset}
   end
 
   defp cron__148(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, comb__offset)
@@ -1057,10 +1093,12 @@ defp cron__150(rest, acc, stack, context, line, offset) do
   end
 
   defp cron__149(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__151(rest, acc, stack, context, line, offset)
   end
 
   defp cron__151(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__152(rest, [] ++ acc, stack, context, line, offset)
   end
 
@@ -1078,7 +1116,7 @@ defp cron__155(<<",", rest::binary>>, acc, stack, context, comb__line, comb__off
 
   defp cron__155(rest, _acc, _stack, context, line, offset) do
     {:error,
-     "expected string \"*\" or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"/\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9 or string \"*\" or string \",\"",
+     "expected string \"*\" or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"/\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or string \"*\" or string \",\"",
      rest, context, line, offset}
   end
 
@@ -1150,6 +1188,8 @@ defp cron__167(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__168(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__169(
       rest,
       (
@@ -1164,6 +1204,8 @@ defp cron__168(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__169(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__170(
       rest,
       [
@@ -1235,6 +1277,8 @@ defp cron__178(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__179(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__180(
       rest,
       (
@@ -1297,6 +1341,8 @@ defp cron__186(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__187(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__188(
       rest,
       (
@@ -1311,6 +1357,7 @@ defp cron__187(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__188(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__189(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -1374,6 +1421,8 @@ defp cron__200(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__201(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__202(
       rest,
       (
@@ -1436,6 +1485,8 @@ defp cron__208(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__209(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__210(
       rest,
       (
@@ -1450,6 +1501,7 @@ defp cron__209(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__210(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__211(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -1522,6 +1574,8 @@ defp cron__220(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__221(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__222(
       rest,
       (
@@ -1536,6 +1590,7 @@ defp cron__221(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__222(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__223(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -1628,6 +1683,8 @@ defp cron__239(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__240(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__241(
       rest,
       (
@@ -1642,6 +1699,8 @@ defp cron__240(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__241(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__242(
       rest,
       [
@@ -1713,6 +1772,8 @@ defp cron__250(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__251(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__252(
       rest,
       (
@@ -1775,6 +1836,8 @@ defp cron__258(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__259(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__260(
       rest,
       (
@@ -1789,6 +1852,7 @@ defp cron__259(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__260(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__261(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -1852,6 +1916,8 @@ defp cron__272(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__273(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__274(
       rest,
       (
@@ -1914,6 +1980,8 @@ defp cron__280(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__281(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__282(
       rest,
       (
@@ -1928,6 +1996,7 @@ defp cron__281(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__282(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__283(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -2000,6 +2069,8 @@ defp cron__292(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__293(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__294(
       rest,
       (
@@ -2014,6 +2085,7 @@ defp cron__293(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__294(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__295(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -2046,6 +2118,7 @@ defp cron__226(
   end
 
   defp cron__296(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__297(rest, [hours: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -2063,7 +2136,8 @@ defp cron__299(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, c
   end
 
   defp cron__299(rest, _acc, _stack, context, line, offset) do
-    {:error, "expected byte equal to ?  or equal to 9", rest, context, line, offset}
+    {:error, "expected ASCII character equal to ' ' or equal to '\\t'", rest, context, line,
+     offset}
   end
 
   defp cron__300(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, comb__offset)
@@ -2080,10 +2154,12 @@ defp cron__302(rest, acc, stack, context, line, offset) do
   end
 
   defp cron__301(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__303(rest, acc, stack, context, line, offset)
   end
 
   defp cron__303(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__304(rest, [] ++ acc, stack, context, line, offset)
   end
 
@@ -2101,7 +2177,7 @@ defp cron__307(<<",", rest::binary>>, acc, stack, context, comb__line, comb__off
 
   defp cron__307(rest, _acc, _stack, context, line, offset) do
     {:error,
-     "expected string \"*\" or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"/\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9 or string \"*\" or string \",\"",
+     "expected string \"*\" or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"/\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or string \"*\" or string \",\"",
      rest, context, line, offset}
   end
 
@@ -2173,6 +2249,8 @@ defp cron__319(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__320(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__321(
       rest,
       (
@@ -2187,6 +2265,8 @@ defp cron__320(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__321(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__322(
       rest,
       [
@@ -2258,6 +2338,8 @@ defp cron__330(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__331(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__332(
       rest,
       (
@@ -2320,6 +2402,8 @@ defp cron__338(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__339(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__340(
       rest,
       (
@@ -2334,6 +2418,7 @@ defp cron__339(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__340(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__341(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -2397,6 +2482,8 @@ defp cron__352(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__353(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__354(
       rest,
       (
@@ -2459,6 +2546,8 @@ defp cron__360(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__361(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__362(
       rest,
       (
@@ -2473,6 +2562,7 @@ defp cron__361(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__362(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__363(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -2545,6 +2635,8 @@ defp cron__372(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__373(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__374(
       rest,
       (
@@ -2559,6 +2651,7 @@ defp cron__373(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__374(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__375(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -2651,6 +2744,8 @@ defp cron__391(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__392(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__393(
       rest,
       (
@@ -2665,6 +2760,8 @@ defp cron__392(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__393(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__394(
       rest,
       [
@@ -2736,6 +2833,8 @@ defp cron__402(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__403(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__404(
       rest,
       (
@@ -2798,6 +2897,8 @@ defp cron__410(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__411(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__412(
       rest,
       (
@@ -2812,6 +2913,7 @@ defp cron__411(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__412(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__413(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -2875,6 +2977,8 @@ defp cron__424(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__425(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__426(
       rest,
       (
@@ -2937,6 +3041,8 @@ defp cron__432(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__433(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__434(
       rest,
       (
@@ -2951,6 +3057,7 @@ defp cron__433(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__434(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__435(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -3023,6 +3130,8 @@ defp cron__444(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__445(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__446(
       rest,
       (
@@ -3037,6 +3146,7 @@ defp cron__445(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__446(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__447(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -3069,6 +3179,7 @@ defp cron__378(
   end
 
   defp cron__448(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__449(rest, [days: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -3086,7 +3197,8 @@ defp cron__451(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, c
   end
 
   defp cron__451(rest, _acc, _stack, context, line, offset) do
-    {:error, "expected byte equal to ?  or equal to 9", rest, context, line, offset}
+    {:error, "expected ASCII character equal to ' ' or equal to '\\t'", rest, context, line,
+     offset}
   end
 
   defp cron__452(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, comb__offset)
@@ -3103,10 +3215,12 @@ defp cron__454(rest, acc, stack, context, line, offset) do
   end
 
   defp cron__453(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__455(rest, acc, stack, context, line, offset)
   end
 
   defp cron__455(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__456(rest, [] ++ acc, stack, context, line, offset)
   end
 
@@ -3128,7 +3242,7 @@ defp cron__461(<<",", rest::binary>>, acc, stack, context, comb__line, comb__off
 
   defp cron__461(rest, _acc, _stack, context, line, offset) do
     {:error,
-     "expected string \"JAN\" or string \"FEB\" or string \"MAR\" or string \"APR\" or string \"MAY\" or string \"JUN\" or string \"JUL\" or string \"AUG\" or string \"SEP\" or string \"OCT\" or string \"NOV\" or string \"DEC\" or string \"*\" or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"/\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9 or string \"*\" or string \",\"",
+     "expected string \"JAN\" or string \"FEB\" or string \"MAR\" or string \"APR\" or string \"MAY\" or string \"JUN\" or string \"JUL\" or string \"AUG\" or string \"SEP\" or string \"OCT\" or string \"NOV\" or string \"DEC\" or string \"*\" or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"/\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or string \"*\" or string \",\"",
      rest, context, line, offset}
   end
 
@@ -3200,6 +3314,8 @@ defp cron__473(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__474(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__475(
       rest,
       (
@@ -3214,6 +3330,8 @@ defp cron__474(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__475(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__476(
       rest,
       [
@@ -3285,6 +3403,8 @@ defp cron__484(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__485(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__486(
       rest,
       (
@@ -3347,6 +3467,8 @@ defp cron__492(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__493(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__494(
       rest,
       (
@@ -3361,6 +3483,7 @@ defp cron__493(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__494(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__495(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -3424,6 +3547,8 @@ defp cron__506(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__507(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__508(
       rest,
       (
@@ -3486,6 +3611,8 @@ defp cron__514(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__515(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__516(
       rest,
       (
@@ -3500,6 +3627,7 @@ defp cron__515(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__516(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__517(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -3572,6 +3700,8 @@ defp cron__526(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__527(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__528(
       rest,
       (
@@ -3586,6 +3716,7 @@ defp cron__527(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__528(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__529(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -3659,6 +3790,8 @@ defp cron__532(rest, _acc, stack, context, line, offset) do
   end
 
   defp cron__533(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__534(
       rest,
       [
@@ -3771,6 +3904,8 @@ defp cron__552(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__553(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__554(
       rest,
       (
@@ -3785,6 +3920,8 @@ defp cron__553(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__554(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__555(
       rest,
       [
@@ -3856,6 +3993,8 @@ defp cron__563(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__564(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__565(
       rest,
       (
@@ -3918,6 +4057,8 @@ defp cron__571(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__572(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__573(
       rest,
       (
@@ -3932,6 +4073,7 @@ defp cron__572(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__573(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__574(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -3995,6 +4137,8 @@ defp cron__585(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__586(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__587(
       rest,
       (
@@ -4057,6 +4201,8 @@ defp cron__593(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__594(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__595(
       rest,
       (
@@ -4071,6 +4217,7 @@ defp cron__594(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__595(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__596(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -4143,6 +4290,8 @@ defp cron__605(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__606(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__607(
       rest,
       (
@@ -4157,6 +4306,7 @@ defp cron__606(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__607(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__608(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -4230,6 +4380,8 @@ defp cron__611(rest, _acc, stack, context, line, offset) do
   end
 
   defp cron__612(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__613(
       rest,
       [
@@ -4278,6 +4430,7 @@ defp cron__537(
   end
 
   defp cron__614(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__615(rest, [months: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -4295,7 +4448,8 @@ defp cron__617(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, c
   end
 
   defp cron__617(rest, _acc, _stack, context, line, offset) do
-    {:error, "expected byte equal to ?  or equal to 9", rest, context, line, offset}
+    {:error, "expected ASCII character equal to ' ' or equal to '\\t'", rest, context, line,
+     offset}
   end
 
   defp cron__618(<<x0::integer, rest::binary>>, acc, stack, context, comb__line, comb__offset)
@@ -4312,10 +4466,12 @@ defp cron__620(rest, acc, stack, context, line, offset) do
   end
 
   defp cron__619(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__621(rest, acc, stack, context, line, offset)
   end
 
   defp cron__621(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__622(rest, [] ++ acc, stack, context, line, offset)
   end
 
@@ -4337,7 +4493,7 @@ defp cron__627(<<",", rest::binary>>, acc, stack, context, comb__line, comb__off
 
   defp cron__627(rest, _acc, _stack, context, line, offset) do
     {:error,
-     "expected string \"MON\" or string \"TUE\" or string \"WED\" or string \"THU\" or string \"FRI\" or string \"SAT\" or string \"SUN\" or string \"*\" or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"/\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9, followed by string \"-\", followed by byte in the range ?0..?9, followed by byte in the range ?0..?9 or byte in the range ?0..?9, followed by byte in the range ?0..?9 or string \"*\" or string \",\"",
+     "expected string \"MON\" or string \"TUE\" or string \"WED\" or string \"THU\" or string \"FRI\" or string \"SAT\" or string \"SUN\" or string \"*\" or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"/\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9', followed by string \"-\", followed by ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or ASCII character in the range '0' to '9', followed by ASCII character in the range '0' to '9' or string \"*\" or string \",\"",
      rest, context, line, offset}
   end
 
@@ -4409,6 +4565,8 @@ defp cron__639(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__640(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__641(
       rest,
       (
@@ -4423,6 +4581,8 @@ defp cron__640(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__641(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__642(
       rest,
       [
@@ -4494,6 +4654,8 @@ defp cron__650(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__651(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__652(
       rest,
       (
@@ -4556,6 +4718,8 @@ defp cron__658(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__659(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__660(
       rest,
       (
@@ -4570,6 +4734,7 @@ defp cron__659(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__660(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__661(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -4633,6 +4798,8 @@ defp cron__672(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__673(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__674(
       rest,
       (
@@ -4695,6 +4862,8 @@ defp cron__680(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__681(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__682(
       rest,
       (
@@ -4709,6 +4878,7 @@ defp cron__681(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__682(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__683(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -4781,6 +4951,8 @@ defp cron__692(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__693(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__694(
       rest,
       (
@@ -4795,6 +4967,7 @@ defp cron__693(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__694(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__695(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -4848,6 +5021,8 @@ defp cron__698(rest, _acc, stack, context, line, offset) do
   end
 
   defp cron__699(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__700(
       rest,
       [
@@ -4960,6 +5135,8 @@ defp cron__718(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__719(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__720(
       rest,
       (
@@ -4974,6 +5151,8 @@ defp cron__719(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__720(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__721(
       rest,
       [
@@ -5045,6 +5224,8 @@ defp cron__729(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__730(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__731(
       rest,
       (
@@ -5107,6 +5288,8 @@ defp cron__737(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__738(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__739(
       rest,
       (
@@ -5121,6 +5304,7 @@ defp cron__738(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__739(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__740(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -5184,6 +5368,8 @@ defp cron__751(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__752(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__753(
       rest,
       (
@@ -5246,6 +5432,8 @@ defp cron__759(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__760(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__761(
       rest,
       (
@@ -5260,6 +5448,7 @@ defp cron__760(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__761(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__762(rest, [range: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -5332,6 +5521,8 @@ defp cron__771(rest, acc, [count | stack], context, line, offset) do
   end
 
   defp cron__772(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__773(
       rest,
       (
@@ -5346,6 +5537,7 @@ defp cron__772(rest, user_acc, [acc | stack], context, line, offset) do
   end
 
   defp cron__773(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__774(rest, [step: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end
 
@@ -5399,6 +5591,8 @@ defp cron__777(rest, _acc, stack, context, line, offset) do
   end
 
   defp cron__778(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
+
     cron__779(
       rest,
       [
@@ -5447,6 +5641,7 @@ defp cron__703(
   end
 
   defp cron__780(rest, user_acc, [acc | stack], context, line, offset) do
+    _ = user_acc
     cron__781(rest, [weekdays: :lists.reverse(user_acc)] ++ acc, stack, context, line, offset)
   end

I now remember that last time I manually renamed the unused user_acc variables to prevent the warnings.

[sorentwo]

Oops. Ignore everything I just wrote. The compile time warnings came while I was compiling nimble_parsec in order to run the compilation step. The version after that diff has no compile warnings, so 🎉