From 9259fef2498433914a521565956635b283c1b5df Mon Sep 17 00:00:00 2001
From: Zachary Snow <zach@zachjs.com>
Date: Fri, 22 Mar 2019 02:01:48 -0400
Subject: [PATCH] tolerate spaces in numeric literals in line with the spec

---
 src/Language/SystemVerilog/Parser/Lex.x         | 16 +++++++---------
 src/Language/SystemVerilog/Parser/Preprocess.hs |  9 ++++++++-
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/src/Language/SystemVerilog/Parser/Lex.x b/src/Language/SystemVerilog/Parser/Lex.x
index 08c7d5d..2bf837f 100644
--- a/src/Language/SystemVerilog/Parser/Lex.x
+++ b/src/Language/SystemVerilog/Parser/Lex.x
@@ -27,20 +27,18 @@ $decimalDigit = [0-9]
 
 @unsignedNumber = $decimalDigit ("_" | $decimalDigit)*
 
-@size = @unsignedNumber
+@size = @unsignedNumber " "?
 
-@decimalNumber
-  = @unsignedNumber
-  | @size? @decimalBase @unsignedNumber
-
-@binaryNumber = @size? @binaryBase @binaryValue
-@octalNumber  = @size? @octalBase  @octalValue
-@hexNumber    = @size? @hexBase    @hexValue
+@decimalNumber = @size? @decimalBase " "? @unsignedNumber
+@binaryNumber  = @size? @binaryBase  " "? @binaryValue
+@octalNumber   = @size? @octalBase   " "? @octalValue
+@hexNumber     = @size? @hexBase     " "? @hexValue
 
 @unbasedUnsizedLiteral = "'" ( 0 | 1 | x | X | z | Z )
 
 @number
-  = @decimalNumber
+  = @unsignedNumber
+  | @decimalNumber
   | @octalNumber
   | @binaryNumber
   | @hexNumber
diff --git a/src/Language/SystemVerilog/Parser/Preprocess.hs b/src/Language/SystemVerilog/Parser/Preprocess.hs
index 86cb801..69828df 100644
--- a/src/Language/SystemVerilog/Parser/Preprocess.hs
+++ b/src/Language/SystemVerilog/Parser/Preprocess.hs
@@ -24,7 +24,14 @@ unskippableDirectives :: [String]
 unskippableDirectives = ["else", "elsif", "endif"]
 
 preprocess :: [Token] -> (StateT PP IO) [Token]
-preprocess tokens = pp tokens
+preprocess tokens = pp tokens >>= return . combineNumbers
+
+-- a bit of a hack to allow things like: `WIDTH'b0
+combineNumbers :: [Token] -> [Token]
+combineNumbers (Token Lit_number size pos : Token Lit_number ('\'' : num) _ : tokens) =
+    Token Lit_number (size ++ "'" ++ num) pos : combineNumbers tokens
+combineNumbers (token : tokens) = token : combineNumbers tokens
+combineNumbers [] = []
 
 data Cond
     = CurrentlyTrue