implement "if" statements with 2 operands (comparing for equality)

src/chat.rs

@@ -679,7 +679,7 @@ pub fn handle_chat_events(
                 }
             }
             ChatEvent::GotoIf(condition, goto) => {
-                if vars.evaluate(condition, &chat.talker.actor_id) {
+                if vars.evaluate_condition(condition, &chat.talker.actor_id) {
                     chat.position = goto.clone();
                 }
             }

src/chats/startrans.yaml

@@ -7,7 +7,7 @@
 
 
 - chat: ClippyTransSerenity
-- set: busstop serenity
+- set: $busstop serenity
 - Welcome at StarTrans Cargo Services!  You have reached Serenity Station.
 - "Ready for a trip?  Available bus stops: Oscillation Station, Metis Prime Station"
 - label: startransbusstop
@@ -21,7 +21,7 @@
 
 
 - chat: ClippyTransMetis
-- set: busstop metis
+- set: $busstop metis
 - Welcome at StarTrans Cargo Services!  You have reached Metis Prime Station.
 - "Ready for a trip?  Available bus stops: Oscillation Station, Serenity Station"
 - label: startransbusstop
@@ -36,7 +36,7 @@
 
 
 - chat: ClippyTransOscillation
-- set: busstop oscillation
+- set: $busstop oscillation
 - Welcome at StarTrans Cargo Services!  You have reached Oscillation Station.
 - "Ready for a trip?  Available bus stops: Serenity Station, Metis Prime Station"
 - label: startransbusstop
@@ -57,21 +57,21 @@
 - Can I take a spacecraft with me?:
   - Absolutely.
   - goto: startransbusstop
-- if: busstop != "oscillation"
+- if: $busstop != oscillation
   Take me to Oscillation Station, please.:
   - StarTrans wishes you a pleasant journey.
   - script: cryofadeout
   - sleep: 5
   - script: cryotrip oscillation
   - goto: EXIT
-- if: busstop != "metis"
+- if: $busstop != metis
   Take me to Metis Prime Station, please.:
   - StarTrans wishes you a pleasant journey.
   - script: cryofadeout
   - sleep: 5
   - script: cryotrip metisprime
   - goto: EXIT
-- if: busstop != "serenity"
+- if: $busstop != serenity
   Take me to Serenity Station, please.:
   - StarTrans wishes you a pleasant journey.
   - script: cryofadeout

src/var.rs

@@ -237,6 +237,7 @@ impl GameVars {
 
     // This method ensures that the variable name contains a scope separator,
     // and if a scope is missing, it prefixes the fallback scope.
+    // Should NOT be used on non-variable values, like plain strings.
     //
     // Some examples, assuming fallback_scope="Clippy", SCOPE_SEPARATOR="$":
     //
@@ -278,9 +279,11 @@ impl GameVars {
         self.db.insert(key, value);
     }
 
-    pub fn evaluate(&self, condition: &str, scope: &str) -> bool {
+    pub fn evaluate_condition(&self, condition: &str, scope: &str) -> bool {
         let parts: Vec<&str> = condition.split(" ").collect();
         if parts.len() == 1 {
+            // Got something like "if $somevar:".
+            // Check whether the variable evaluates to true.
             let part = parts[0];
             if part.contains(SCOPE_SEPARATOR) {
                 let part = Self::normalize_varname(scope, part);
@@ -290,6 +293,26 @@ impl GameVars {
             else {
                 return Self::evaluate_str_as_bool(part);
             }
+
+        } else if parts.len() == 2 {
+            // Got something like "if $something somethingelse"
+            // Check whether the two are identical.
+            let mut left: String = parts[0].to_string();
+            if left.contains(SCOPE_SEPARATOR) {
+                left = self
+                    .get(Self::normalize_varname(scope, left.as_str()).as_str())
+                    .unwrap_or("".to_string());
+            }
+            let mut right: String = parts[1].to_string();
+            if right.contains(SCOPE_SEPARATOR) {
+                right = self
+                    .get(Self::normalize_varname(scope, right.as_str()).as_str())
+                    .unwrap_or("".to_string());
+            }
+            dbg!(&left);
+            dbg!(&right);
+            dbg!(left == right);
+            return left == right;
         } else {
             return false;
         }