interpreter: concatenation; proper type display

interpreter/src/ir.rs

@@ -224,6 +224,7 @@ impl OpCode {
                 | Self::Divide
                 | Self::Raise
                 | Self::Modulo
+                | Self::Concat
         )
     }
 

interpreter/src/types.rs

@@ -1,6 +1,8 @@
 use std::{
     borrow::Cow,
+    fmt::Display,
     hash::Hash,
+    io::Write,
     mem::discriminant,
     ops::{Add, Div, Mul, Sub},
 };
@@ -62,6 +64,26 @@ impl Value<'_> {
             _ => 0.,
         }
     }
+
+    pub fn write_string(&self, f: &mut Vec<u8>) {
+        match self {
+            Self::String(s) | Self::Regex(s) => f.extend_from_slice(s),
+            Self::Float(n) => write!(f, "{n}").unwrap(),
+            &Self::Bool(false) => f.push(b'0'),
+            &Self::Bool(true) => f.push(b'1'),
+            Self::Array(_) => panic!("Attempted to use array in scalar context!"),
+            _ => {}
+        }
+    }
+
+    pub fn string_size_hint(&self) -> usize {
+        match self {
+            Self::String(s) | Self::Regex(s) => s.len(),
+            Self::Float(_) => 2,
+            Self::Bool(_) => 1,
+            _ => 0,
+        }
+    }
 }
 
 impl<'a> Add for &'_ Value<'a> {
@@ -109,3 +131,17 @@ impl Hash for Value<'_> {
         }
     }
 }
+
+impl Display for Value<'_> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Value::Float(n) => <_ as Display>::fmt(n, f),
+            Value::String(s) => write!(f, "{:?}", String::from_utf8_lossy(s)),
+            Value::Regex(s) => write!(f, "/{}/", String::from_utf8_lossy(s)),
+            &Value::Bool(b) => write!(f, "{}", b as usize),
+            Value::Array(_) => write!(f, "array"),
+            Value::Untyped => write!(f, "untyped"),
+            Value::Unassigned => write!(f, "unassigned"),
+        }
+    }
+}

interpreter/src/vm.rs

@@ -1,6 +1,7 @@
 use std::{
     fmt::{self, Display},
     mem::replace,
+    vec::Vec as StdVec,
 };
 
 use ahash::RandomState;
@@ -117,6 +118,14 @@ impl Interpreter<'_> {
                             OpCode::Subtract => lhs - rhs,
                             OpCode::Multiply => lhs * rhs,
                             OpCode::Divide => lhs / rhs,
+                            OpCode::Concat => {
+                                let mut buf = StdVec::with_capacity(
+                                    lhs.string_size_hint() + rhs.string_size_hint(),
+                                );
+                                lhs.write_string(&mut buf);
+                                rhs.write_string(&mut buf);
+                                Value::String(buf.into())
+                            }
                             _ => todo!(),
                         }
                     };
@@ -203,7 +212,7 @@ impl Display for Registers<'_> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "Registers:")?;
         let n = self.0.len().checked_ilog10().unwrap_or(0) as usize + 1;
-        fmt_list(f, self.0.iter(), |f, i, e| write!(f, "r{i:0n$} = {e:?}"))
+        fmt_list(f, self.0.iter(), |f, i, e| write!(f, "r{i:0n$} = {e}"))
     }
 }
 
@@ -211,7 +220,7 @@ impl Display for SymbolTable<'_> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "Symbols:")?;
         fmt_list(f, self.user.iter(), |f, i, (k, v)| {
-            write!(f, "user[{i}] @ {k} = {v:?}")
+            write!(f, "user[{i}] @ {k} = {v}")
         })
     }
 }
@@ -219,7 +228,7 @@ impl Display for SymbolTable<'_> {
 impl Display for Consts<'_> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "Consts:")?;
-        fmt_list(f, self.0.iter(), |f, i, e| write!(f, "mem[{i}] = {e:?}"))
+        fmt_list(f, self.0.iter(), |f, i, e| write!(f, "mem[{i}] = {e}"))
     }
 }