Working with Data Types

Data types form the foundation of Coldwave Script. Unlike in many high-level languages, they directly influence safety and predictability: integers saturate instead of overflowing, floating-point values follow IEEE rules, time types support precise control logic, and type conversions are strictly defined. Understanding these rules helps avoid surprises and enables deterministic programming.

Integers (signed/unsigned, promotion, overflow)

INT = 16-bit (−32768 … +32767), UINT = 16-bit (0 … 65535), use DINT/LINT for larger signed values, UDINT/ULINT for larger unsigned values.

Special behavior: saturating arithmetic — overflow clamps to the maximum, underflow clamps to minimum (signed) or 0 (unsigned).

PROGRAM  
    DIM a AS INT = 32760  
    DIM b AS INT = 100  
    PRINT a + b ' Output: 32767 (saturated, no overflow)  
END PROGRAM

Promotion rules: operations involving mixed types promote to the wider type
(INT + DINT → DINT, INT + REAL → REAL).

Floating Point (REAL/LREAL)

REAL = 32-bit, LREAL = 64-bit. IEEE 754 compliant. Suitable for physical values with decimals.

PROGRAM  
    PRINT 7 / 2 ' Output: 3 (INT division)  
    PRINT TO_REAL(7) / 2 ' Output: 3.5 (REAL division)  
END PROGRAM

Tip: If fractional results are required, convert first using TO_REAL.

BOOL & Comparisons

BOOL only supports TRUE and FALSE. Comparisons return BOOL. Operators: AND, OR, XOR, NOT.

PROGRAM  
    DIM ok AS BOOL  
    ok = (5 < 7)  
    PRINT ok ' Output: TRUE  
END PROGRAM

TIME / DATE

TIME is stored in milliseconds. Syntax: T#500ms, T#2s, T#1h.

DATE, TOD, DT examples: DATE#2025-01-01, TOD#12:00:00, DT#2025-01-01-12:00:00.

PROGRAM  
    PRINT TO_TIME(1000) ' Output: T#1000ms  
    PRINT ADD_TIME(T#500ms, T#200ms) ' Output: T#700ms  
END PROGRAM

TIME is often used together with blocks like TON.

Type Conversions

All TO_* functions are safety-oriented. Non-representable values are clamped instead of wrapping.

PROGRAM  
    PRINT TO_UINT(-5) ' Output: 0  
    PRINT TO_INT(3.9) ' Output: 3  
    PRINT TO_REAL(42) ' Output: 42.0  
END PROGRAM

Summary

• Integers saturate; unsigned clamps to 0.
• Promotion raises operands to the wider type.
• REAL/LREAL for fractional values; INT division truncates.
• BOOL from comparisons and logical operators.
• TIME/DATE/DT enable time-based logic.
• TO_* conversion functions are safe and deterministic.