[Avg. reading time: 3 minutes]
Strongly Typed vs Weakly Typed
Strongly Typed
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Strongly typed languages do not allow implicit conversion between unrelated types
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Operations on incompatible types require explicit conversion
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Strong typing is about type safety, not when types are checked
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Strong vs weak typing is independent of static vs dynamic typing
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A language can be dynamically typed and still strongly typed Example: Python is strongly typed
#Python
a = 21; #type assigned as int at runtime.
a = a + "dot"; #type-error, string and int cannot be concatenated.
print(a);
Weakly Typed
- Weakly typed languages allow implicit conversions between unrelated types
- The runtime guesses what you meant and proceeds
- This can be convenient and dangerous
Example: JavaScript is weakly typed
/*
As Javascript is a weakly-typed language, it allows implicit conversion
between unrelated types.
*/
a = 21;
a = a + "dot";
console.log(a);
- JavaScript silently converts 21 to “21”
- Result is “21dot”
- No error, no warning
