sanitize user input

src/procedures.nim

@@ -1,5 +1,19 @@
 import strutils, sequtils
 
+proc getInt(): int =
+    while(true):
+        try:
+            return parseInt(readline(stdin))
+        except:
+            echo "Please enter an integer, try again."
+
+proc getFloat(): float =
+    while(true):
+        try:
+            return parseFloat(readline(stdin))
+        except:
+            echo "Please enter a number, try again."
+
 #? prints a matrix to the standard output
 proc printMatrix*(matrix: seq[seq[float]]) =
     let row: int = matrix.len
@@ -11,8 +25,8 @@ proc fillMatrix*(matrix: var seq[seq[float]], row, col: int) =
     for i in countup(1, row):
         for j in countup(1, col):
             echo "Enter item:"
-            var entry: float = parseFloat(readLine(stdin)) # TODO: while loop to check if input is valid
-            matrix[i-1].add(entry)
+            # var entry: float = getFloat() # TODO: while loop to check if input is valid
+            matrix[i-1].add(getFloat())
             matrix[i-1].delete(0)
         echo matrix[i-1]
 
@@ -50,9 +64,9 @@ proc dot*() =
 
     #? record first matrix
     echo "Enter number of rows in the first matrix:"
-    let r1: int = parseInt(readLine(stdin)) 
+    let r1: int = getInt() 
     echo "Enter number of columns in the first matrix:"
-    let c1: int = parseInt(readLine(stdin))
+    let c1: int = getInt()
     var m1 = newSeqWith(r1, newSeq[float](c1))
     procedures.fillMatrix(m1, r1, c1)
 
@@ -60,9 +74,9 @@ proc dot*() =
 
     #? record second matrix
     echo "Enter number of rows in the second matrix:"
-    let r2: int = parseInt(readLine(stdin))
+    let r2: int = getInt()
     echo "Enter number of columns in the second matrix:"
-    let c2: int = parseInt(readLine(stdin))
+    let c2: int = getInt()
     var m2 = newSeqWith(r2, newSeq[float](c2))
     procedures.fillMatrix(m2, r2, c2)
 
@@ -89,12 +103,12 @@ proc cross*() =
     echo "Enter numbers in the first vector:"
     for i in 0..2:
         echo "Enter item:"
-        v1[i] = parseFloat(readLine(stdin))
+        v1[i] = getFloat()
 
     echo "Enter numbers in the second vector:"
     for i in 0..2:
         echo "Enter item:"
-        v2[i] = parseFloat(readLine(stdin))
+        v2[i] = getFloat()
 
     #? resultent vector
     let v = calcCross(v1, v2)