Extract Hour & Minute from Time

extractHourMinute

Extracts the hour and minute components from a time string in HH:MM or -HH:MM format and returns them as a numeric tuple.

Function Signature

function extractHourMinute(time: `-${Time}` | Time): [number, number];

Parameters

• time: A string in either:
  • Positive format: HH:MM (e.g., "08:30")
  • Negative format: -HH:MM (e.g., "-05:00")

Return Value

A tuple containing:

1. Hour component (number)
2. Minute component (number)

Example Usage

import { extractHourMinute } from 'nhb-toolbox';

// Positive time
const [hour1, minute1] = extractHourMinute("14:45");
console.log(hour1);    // 14
console.log(minute1);  // 45

// Negative time
const [hour2, minute2] = extractHourMinute("-03:30");
console.log(hour2);    // -3
console.log(minute2);  // 30

Notes

• Handles both positive and negative time formats
• Returns raw numbers (negative sign preserved for hour)
• Uses strict type checking for valid time formats
• Follows 24-hour time format conventions
• Minute component always positive (0-59)

Type Safety

The input type ensures only valid formats are accepted:

type Time = `${Hours}:${Minutes}`;  // HH:MM format
type Hours = '00'|'01'|...|'23';    // Valid hours
type Minutes = '00'|'01'|...|'59';  // Valid minutes

Edge Cases

• "00:00" returns [0, 0]
• "-00:30" returns [0, 30] (negative zero becomes zero)
• "23:59" returns [23, 59]

Use Cases

• Time manipulation utilities
• Timezone offset calculations
• Duration parsing
• Scheduling applications
• Time-based validation

Conclusion

The extractHourMinute function provides:

1. Strict input validation through types
2. Simple time component extraction
3. Consistent numeric output
4. Flexible handling of signed times

Ideal for applications requiring:

• Precise time parsing
• Time arithmetic operations
• Timezone conversions
• Duration calculations