all: initial interpreter code (#12605)

vlib/v/eval/object.v

@@ -0,0 +1,150 @@
+module eval
+
+const empty = Void{}
+
+// NB: i64 is an int_literal, NOT an i64 (same with f64)
+type Object = Array
+	| Float
+	| Int
+	| Ptr
+	| Uint
+	| Void
+	| []Object
+	| bool
+	| byte
+	| char
+	| f64
+	| i64
+	| rune
+	| string
+	| voidptr
+
+// string is the same as the autogenerated str() methods
+pub fn (o Object) string() string {
+	match o {
+		byte {
+			panic('error: byte should only be used for &byte')
+		}
+		bool {
+			return o.str()
+		}
+		i64 { // int_literal
+			return o.str()
+		}
+		f64 { // float_literal
+			return o.str()
+		}
+		Int {
+			return o.val.str()
+		}
+		Uint {
+			return o.val.str()
+		}
+		Float {
+			return o.val.str()
+		}
+		string {
+			return o
+		}
+		Void {
+			return ''
+		}
+		[]Object {
+			mut res := '('
+			for i, obj in o {
+				res += obj.str()
+				if i + 1 != o.len {
+					res += ', '
+				}
+			}
+			return res + ')'
+		}
+		voidptr {
+			return o.str()
+		}
+		char {
+			return int(o).str()
+		}
+		rune {
+			return o.str()
+		}
+		Array {
+			mut res := '['
+			for i, val in o.val {
+				res += val.string()
+				if i + 1 != o.val.len {
+					res += ', '
+				}
+			}
+			return res + ']'
+		}
+		Ptr {
+			return o.val.str()
+		}
+	}
+}
+
+pub fn (o Object) int_val() i64 {
+	match o {
+		Int {
+			return o.val
+		}
+		Uint {
+			return i64(o.val)
+		}
+		i64 {
+			return o
+		}
+		else {
+			panic('Object.int_val(): not an int')
+		}
+	}
+}
+
+pub fn (o Object) float_val() f64 {
+	match o {
+		Float {
+			return o.val
+		}
+		f64 {
+			return o
+		}
+		else {
+			panic('Object.float_val(): not a float')
+		}
+	}
+}
+
+struct Void {}
+
+pub struct Int {
+pub mut:
+	val  i64
+	size i8 // 8/16/32/64
+}
+
+pub struct Uint {
+pub mut:
+	val  u64
+	size i8 // 8/16/32/64
+}
+
+pub struct Float {
+pub mut:
+	val  f64
+	size i8 // 8/16/32/64
+}
+
+pub struct Array {
+pub mut:
+	val []Object
+}
+
+pub struct Ptr {
+	val &Object
+}
+
+// override the autogenerated str, since it does not work
+fn (p Ptr) str() string {
+	return u64(p.val).str()
+}