feat: added optional profiling

internal/config/config.go

@@ -2,10 +2,8 @@ package config
 
 // Arguments given to program.
 type Config struct {
-	// The source code given to the program.
-	Source Source
-	// Whether or not to print debug logs.
-	Verbose bool
-	// Whether or not to print an explanation of the reduction.
-	Explanation bool
+	Source      Source // The source code given to the program.
+	Verbose     bool   // Whether or not to print debug logs.
+	Explanation bool   // Whether or not to print an explanation of the reduction.
+	Profile     string // If not nil, print a CPU profile during execution.
 }