small changes

src/asm.rs

@@ -100,7 +100,7 @@ pub fn assemble(input: &str) -> Result<Vec<Word>, TaggedAsmError> {
   if let Some(l) = last {
     Err(TaggedAsmError {
       kind: AsmError::ExpectedNum,
-      word: l.to_string(),
+      word: "[END OF FILE]".to_string(),
     })
   } else {
     Ok(output)

src/lib.rs

@@ -18,6 +18,7 @@ pub struct Machine {
   ip: Word,
   ebp: Word,
   phase: Phase,
+  clock: usize,
   pub log: String,
   pub cstack: Vec<Word>,
   pub pstack: Vec<Word>,
@@ -32,6 +33,7 @@ impl Machine {
       ip: 0,
       ebp: 0,
       phase: Phase::Warmup,
+      clock: 0,
       log: "".to_string(),
       cstack: vec![],
       pstack: vec![],
@@ -106,6 +108,10 @@ impl Machine {
   }
 
   pub fn step(&mut self) -> CResult {
+    self.clock += 1;
+    if self.clock > 256 {
+      return Err(Error::ExecLimit)
+    }
     let word = self
       .instructions
       .get(self.ip as usize)
@@ -363,7 +369,7 @@ impl Machine {
         self.phase = Phase::Recital;
         self.ip = match self.fstack.last() {
           Some(i) => *i,
-          None => return Err(Error::StackUnderflow),
+          None => return Err(Error::NoFunc),
         }
       },
       OpKind::Push => {

src/util.rs

@@ -18,6 +18,8 @@ pub enum Error {
   BadCall,
   NoExec,
   IllegalOp,
+  NoFunc,
+  ExecLimit,
   EndReached,
 }
 
@@ -30,13 +32,18 @@ impl Display for Error {
       Self::WriteOob => write!(f, "Memory write out of bounds"),
       Self::ReadOob => write!(f, "Memory read out of bounds"),
       Self::IllegalOp => write!(f, "Illegal instruction reached"),
+
       Self::BadCall => {
         write!(f, "Attempted to call function which does not exist")
       },
       Self::NoExec => write!(
         f,
-        "No exec instruction found. Are you trying to execute a library?"
+        "No exe instruction found. Are you trying to execute a library?"
       ),
+      Self::NoFunc => {
+        write!(f, "Cannot begin Recital, no functions have been defined")
+      },
+      Self::ExecLimit => write!(f, "Execution limit reached, compile and run natively to do really big stuff!"),
       Self::EndReached => write!(f, "Successfully terminated"),
     }
   }