input()

The input() function in Zard reads a value from standard input (stdin) and adapts its type based on the context where it is used. You do not specify the type of input() directly: instead, the compiler specializes it according to the expected type at that location.

In other words: input() is polymorphic and type-directed. For each concrete use (e.g. assigning to int, double, string), the compiler generates a dedicated model/handler for that type.

Type-directed behavior

When the compiler sees input(), it looks at the expected type in that position and specializes the call:

• Assigning to int → generates an integer input reader.
• Assigning to double → generates a floating-point input reader.
• Assigning to string → generates a string input reader.
• Assigning to char → generates a char input reader.
• Assigning to float → generates a float input reader.

This behavior is resolved at compile time. No explicit cast is required, and input() itself remains syntactically the same in all cases.

main {

    int a = input();      # input specialized as int reader
    double c = input();   # input specialized as double reader

    print(c);
    print(a);
}
      

In the example above, the same input() syntax results in two different internal models: one for int, one for double.

Behavior and runtime notes

• input() is blocking: the program waits until the user provides a value.
• The concrete parsing (for int, double, string, etc.) is performed by the generated runtime helpers.
• If the user types something incompatible with the expected type (e.g. letters when an int is expected), the current behavior depends on the implementation/runtime and may result in an error.

Internally, the compiler may generate different low-level functions or LLVM helpers for each observed usage of input(), effectively creating a dedicated model per case of use.

Summary

• input() has no explicit type annotation in the code.
• The type is inferred from the variable or expression that receives the value.
• The compiler specializes and generates a dedicated reader for each type context.