diff --git a/forge_core/src/ast.rs b/forge_core/src/ast.rs
index 5e5e86a..d1065e9 100644
--- a/forge_core/src/ast.rs
+++ b/forge_core/src/ast.rs
@@ -9,36 +9,36 @@ pub enum Declaration {
     Const(Const),
 }
 
-#[derive(Eq, PartialEq, Clone, Debug, Default)]
+#[derive(PartialEq, Clone, Debug, Default)]
 pub struct Varinfo {
     pub typename: Option<String>,
-    pub size: Option<i32>,
+    pub size: Option<Node>,
 }
 
-#[derive(Eq, PartialEq, Clone, Debug)]
+#[derive(PartialEq, Clone, Debug)]
 pub struct Global {
     pub name: String,
     pub typename: Option<String>,
-    pub size: Option<i32>,
+    pub size: Option<Node>,
 }
 
-#[derive(Eq, PartialEq, Clone, Debug)]
+#[derive(PartialEq, Clone, Debug)]
 pub struct Struct {
     pub name: String,
     pub members: Vec<Member>,
 }
 
-#[derive(Eq, PartialEq, Clone, Debug)]
+#[derive(PartialEq, Clone, Debug)]
 pub struct Member {
     pub name: String,
     pub typename: Option<String>,
-    pub size: Option<i32>,
+    pub size: Option<Node>,
 }
 
-#[derive(Eq, PartialEq, Clone, Debug)]
+#[derive(PartialEq, Clone, Debug)]
 pub struct Const {
     pub name: String,
-    pub value: Option<i32>, // todo: this should take a Node
+    pub value: Option<Node>,
     pub string: Option<String>,
 }
 
@@ -103,7 +103,7 @@ pub enum Rvalue {
 pub struct VarDecl {
     pub name: String,
     pub typename: Option<String>,
-    pub size: Option<i32>,
+    pub size: Option<Node>,
     pub initial: Option<Node>,
 }
 
diff --git a/forge_core/src/forge.pest b/forge_core/src/forge.pest
index 5e74b11..f69d615 100644
--- a/forge_core/src/forge.pest
+++ b/forge_core/src/forge.pest
@@ -5,14 +5,11 @@ name_char = { ASCII_ALPHA_LOWER | ASCII_ALPHA_UPPER | "_" | "$" }
 name = @{ name_char ~ (name_char | ASCII_DIGIT)* }
 
 dec_number = @{ ASCII_NONZERO_DIGIT ~ ASCII_DIGIT* }
-// Literal numbers use this rule, but in exprs it's the prefix operator. The difference
-// is that some things (const initialization) only accept literal numbers.
-neg_number = ${ "-" ~ dec_number }
 hex_number = ${ "0x" ~ ASCII_HEX_DIGIT+ }
 bin_number = ${ "0b" ~ ASCII_BIN_DIGIT+ }
 oct_number = ${ "0o" ~ ASCII_OCT_DIGIT+ }
 dec_zero = @{ "0" }
-number = { dec_number | hex_number | bin_number | oct_number | dec_zero | neg_number }
+number = { dec_number | hex_number | bin_number | oct_number | dec_zero }
 
 escape = @{ "\\" ~ ("t" | "r" | "n" | "0" | "\\" | "\"") }
 string_inner = ${ !("\"" | "\\") ~ ANY | escape }
@@ -90,8 +87,8 @@ repeat_loop = { "repeat" ~ "(" ~ expr ~ ")" ~ name? ~ block }
 var_decl = { "var" ~ name ~ varinfo ~ ("=" ~ expr)? }
 global = { "global" ~ name ~ varinfo ~ ";" }
 typename = { ":" ~ name }
-size = { "[" ~ number ~ "]" }
-const_decl = { "const" ~ name ~ "=" ~ (number | string) ~ ";" }
+size = { "[" ~ expr ~ "]" }
+const_decl = { "const" ~ name ~ "=" ~ (expr | string) ~ ";" }
 
 struct_decl = { "struct" ~ name ~ "{" ~ members ~ "}" }
 member = { name ~ varinfo }
diff --git a/forge_core/src/forge_parser.rs b/forge_core/src/forge_parser.rs
index c9ccee9..ca50a03 100644
--- a/forge_core/src/forge_parser.rs
+++ b/forge_core/src/forge_parser.rs
@@ -66,9 +66,7 @@ impl<'a> PairExt for Pair<'a> {
     fn into_number(self) -> i32 {
         let first = self.into_inner().next().unwrap();
         match first.as_rule() {
-            Rule::dec_number | Rule::dec_zero | Rule::neg_number => {
-                i32::from_str(first.as_str()).unwrap()
-            }
+            Rule::dec_number | Rule::dec_zero => i32::from_str(first.as_str()).unwrap(),
             Rule::hex_number => i32::from_str_radix(first.as_str().get(2..).unwrap(), 16).unwrap(),
             Rule::bin_number => i32::from_str_radix(first.as_str().get(2..).unwrap(), 2).unwrap(),
             Rule::oct_number => i32::from_str_radix(first.as_str().get(2..).unwrap(), 8).unwrap(),
@@ -177,7 +175,7 @@ impl AstNode for Varinfo {
             .map(|t| String::from(t.first().as_str()));
         let size = children
             .next_if_rule(Rule::size)
-            .map(|s| s.first().into_number());
+            .map(|s| Node::from_pair(s.first()));
         Self { typename, size }
     }
 }
@@ -241,10 +239,10 @@ impl AstNode for Const {
                 string: Some(value.into_quoted_string()),
                 value: None,
             },
-            Rule::number => Const {
+            Rule::expr => Const {
                 name,
                 string: None,
-                value: Some(value.into_number()),
+                value: Some(Node::from_pair(value)),
             },
             _ => unreachable!(),
         }
@@ -576,7 +574,7 @@ mod test {
             Ok(Global {
                 name: "foo".into(),
                 typename: Some("Thing".into()),
-                size: Some(10)
+                size: Some(Node::Number(10))
             })
         );
         assert_eq!(
@@ -584,7 +582,7 @@ mod test {
             Ok(Global {
                 name: "foo".into(),
                 typename: None,
-                size: Some(10)
+                size: Some(Node::Number(10))
             })
         );
     }
@@ -595,7 +593,7 @@ mod test {
             Const::from_str("const a = 123;"),
             Ok(Const {
                 name: "a".into(),
-                value: Some(123),
+                value: Some(Node::Number(123)),
                 string: None
             })
         );
@@ -603,7 +601,7 @@ mod test {
             Const::from_str("const a = 0xaa;"),
             Ok(Const {
                 name: "a".into(),
-                value: Some(0xaa),
+                value: Some(Node::Number(0xaa)),
                 string: None
             })
         );
@@ -611,7 +609,10 @@ mod test {
             Const::from_str("const a = -7;"),
             Ok(Const {
                 name: "a".into(),
-                value: Some(-7),
+                value: Some(Node::Prefix(
+                    crate::ast::Prefix::Neg,
+                    Node::Number(7).into()
+                )),
                 string: None
             })
         );
@@ -653,7 +654,7 @@ mod test {
                 members: vec![Member {
                     name: "bar".into(),
                     typename: None,
-                    size: Some(100)
+                    size: Some(Node::Number(100))
                 },]
             })
         );
@@ -665,7 +666,7 @@ mod test {
                 members: vec![Member {
                     name: "bar".into(),
                     typename: Some("Thing".into()),
-                    size: Some(100)
+                    size: Some(Node::Number(100))
                 },]
             })
         );
@@ -963,7 +964,7 @@ mod test {
             Ok(VarDecl {
                 name: "blah".into(),
                 typename: Some("Foo".into()),
-                size: Some(7),
+                size: Some(Node::Number(7)),
                 initial: Some(Node::Number(35)),
             })
         );