fix ln and remove unused code

src/built-ins.go

@@ -1,5 +1,7 @@
 package main
 
+import "github.com/wadey/go-rounding"
+
 var vars = scope{}
 
 func init() {
@@ -65,11 +67,68 @@ func init() {
 		}
 		return nil, ArErr{TYPE: "TypeError", message: "Cannot create array from '" + typeof(a[0]) + "'", EXISTS: true}
 	}}
-	vars["maths"] = maths
-	vars["math"] = maths
 	vars["time"] = ArTime
 	vars["PI"] = PI
 	vars["π"] = PI
 	vars["e"] = e
+	vars["ln"] = builtinFunc{"ln", ArgonLn}
+	vars["log"] = builtinFunc{"log", ArgonLog}
+	vars["logN"] = builtinFunc{"logN", ArgonLogN}
 	vars["thread"] = builtinFunc{"thread", ArThread}
+	vars["round"] = builtinFunc{"round", func(a ...any) (any, ArErr) {
+		if len(a) == 0 {
+			return nil, ArErr{TYPE: "round", message: "round takes 1 argument",
+				EXISTS: true}
+		}
+		precision := newNumber()
+		if len(a) > 1 {
+			switch x := a[1].(type) {
+			case number:
+				if !x.IsInt() {
+					return nil, ArErr{TYPE: "TypeError", message: "Cannot round to '" + typeof(a[1]) + "'", EXISTS: true}
+				}
+				precision = x
+			default:
+				return nil, ArErr{TYPE: "TypeError", message: "Cannot round to '" + typeof(a[1]) + "'", EXISTS: true}
+			}
+		}
+
+		switch x := a[0].(type) {
+		case number:
+			return rounding.Round(newNumber().Set(x), int(precision.Num().Int64()), rounding.HalfUp), ArErr{}
+		}
+		return nil, ArErr{TYPE: "TypeError", message: "Cannot round '" + typeof(a[0]) + "'", EXISTS: true}
+	}}
+	vars["floor"] = builtinFunc{"floor", func(a ...any) (any, ArErr) {
+		if len(a) == 0 {
+			return nil, ArErr{TYPE: "floor", message: "floor takes 1 argument",
+				EXISTS: true}
+		}
+		switch x := a[0].(type) {
+		case number:
+			n := newNumber().Set(x)
+			if n.Sign() < 0 {
+				return rounding.Round(n, 0, rounding.Up), ArErr{}
+			}
+			return rounding.Round(n, 0, rounding.Down), ArErr{}
+		}
+		return nil, ArErr{TYPE: "TypeError", message: "Cannot floor '" + typeof(a[0]) + "'", EXISTS: true}
+	}}
+	vars["ceil"] = builtinFunc{"ceil", func(a ...any) (any, ArErr) {
+		if len(a) == 0 {
+			return nil, ArErr{TYPE: "ceil", message: "ceil takes 1 argument",
+				EXISTS: true}
+		}
+
+		switch x := a[0].(type) {
+		case number:
+			n := newNumber().Set(x)
+			if n.Sign() < 0 {
+				return rounding.Round(n, 0, rounding.Down), ArErr{}
+			}
+			return rounding.Round(n, 0, rounding.Up), ArErr{}
+		}
+		return nil, ArErr{TYPE: "TypeError", message: "Cannot ceil '" + typeof(a[0]) + "'", EXISTS: true}
+	}}
+	vars["sqrt"] = builtinFunc{"sqrt", ArgonSqrt}
 }