Add metadata entities

entity/literal.go

@@ -1,7 +1,6 @@
 package entity
 
 import "fmt"
-import "unicode"
 import "git.tebibyte.media/sashakoshka/fspl/errors"
 
 // LiteralInt specifies an integer value. It can be assigned to any type that is
@@ -69,17 +68,7 @@ type LiteralString struct {
 func (*LiteralString) expression(){}
 func (this *LiteralString) Type () Type { return this.Ty }
 func (this *LiteralString) String () string {
-	out := "'"
-	for _, char := range this.ValueUTF8 {
-		if char == '\'' {
-			out += "\\'"
-		} else if unicode.IsPrint(char) {
-			out += string(char)
-		} else {
-			out += fmt.Sprintf("\\%03o", char)
-		}
-	}
-	return out + "'"
+	return Quote(this.ValueUTF8)
 }
 
 // LiteralArray is a composite array literal. It can contain any number of

entity/meta.go

@@ -0,0 +1,29 @@
+package entity
+
+import "fmt"
+import "git.tebibyte.media/sashakoshka/fspl/errors"
+
+// Dependency is a metadata dependency listing.
+type Dependency struct {
+	Position errors.Position
+	Address  Address
+	Nickname Nickname
+}
+
+func (this *Dependency) String () string {
+	return fmt.Sprint()
+}
+
+// Address is the address of a unit.
+type Address string
+
+func (addr Address) String () string {
+	return Quote(string(addr))
+}
+
+// Nickname is the nickname of a unit.
+type Nickname string
+
+func (nick Nickname) String () string {
+	return string(nick)
+}

entity/misc.go

@@ -1,6 +1,7 @@
 package entity
 
 import "fmt"
+import "unicode"
 import "git.tebibyte.media/sashakoshka/fspl/errors"
 
 // Signature is a function or method signature that is used in functions,
@@ -137,3 +138,18 @@ func OperatorFromString (str string) Operator {
 func (this Operator) String () string {
 	return operatorToString[this]
 }
+
+// Quote puts quotes around a string to turn it into a string literal.
+func Quote (in string) string {
+	out := "'"
+	for _, char := range in {
+		if char == '\'' {
+			out += "\\'"
+		} else if unicode.IsPrint(char) {
+			out += string(char)
+		} else {
+			out += fmt.Sprintf("\\%03o", char)
+		}
+	}
+	return out + "'"
+}