Function Utilities

The fnutils package provides utilities for working with functions in Go. It includes helpers for delayed function execution and other common function-related operations.

Features

Delayed Execution: Execute functions after specified time intervals
Multiple Time Units: Support for various time units (seconds, milliseconds, minutes)
Error Handling: Consistent error handling for function execution
Simple API: Easy-to-use interface for common function operations

Core Functions

Delayed Execution

The package provides several functions for executing a given function after a specific time delay:

ExecuteAfterSecs(fn func(), timeout int) error: Execute a function after the specified number of seconds
ExecuteAfterMs(fn func(), timeout int64) error: Execute a function after the specified number of milliseconds
ExecuteAfterMin(fn func(), timeout int) error: Execute a function after the specified number of minutes
ExecuteAfter(fn func(), timeout time.Duration) error: Base function that executes a function after the specified time duration

Usage Examples

Basic Delayed Execution

package main

import (
    "fmt"
    "oss.nandlabs.io/golly/fnutils"
)

func main() {
    // Execute a function after 5 seconds
    err := fnutils.ExecuteAfterSecs(func() {
        fmt.Println("This will be printed after 5 seconds")
    }, 5)

    if err != nil {
        fmt.Printf("Error: %v\n", err)
    }

    // Keep the program running
    fmt.Println("Waiting...")
    // In a real application, you might wait using another mechanism
}

Using Different Time Units

package main

import (
    "fmt"
    "oss.nandlabs.io/golly/fnutils"
)

func main() {
    // Execute after 2000 milliseconds (2 seconds)
    fnutils.ExecuteAfterMs(func() {
        fmt.Println("Executed after 2000 milliseconds")
    }, 2000)

    // Execute after 1 minute
    fnutils.ExecuteAfterMin(func() {
        fmt.Println("Executed after 1 minute")
    }, 1)

    // Keep the program running
    fmt.Println("Waiting...")
    // In a real application, you might wait using another mechanism
}

Error Handling

package main

import (
    "fmt"
    "oss.nandlabs.io/golly/fnutils"
)

func main() {
    // Invalid cases
    err1 := fnutils.ExecuteAfterSecs(nil, 5) // Nil function
    if err1 != nil {
        fmt.Printf("Error 1: %v\n", err1) // Expected: "nil function provided"
    }

    err2 := fnutils.ExecuteAfterSecs(func() {
        fmt.Println("This won't execute")
    }, -10) // Negative timeout

    if err2 != nil {
        fmt.Printf("Error 2: %v\n", err2) // Expected: "timeout cannot be negative"
    }
}

Practical Applications

package main

import (
    "fmt"
    "time"
    "oss.nandlabs.io/golly/fnutils"
)

func main() {
    fmt.Println("Starting a simulated task...")

    // Simulate starting a task
    taskStart := time.Now()

    // Set up a delayed function to check on the task after 3 seconds
    fnutils.ExecuteAfterSecs(func() {
        elapsed := time.Since(taskStart)
        fmt.Printf("Task has been running for %v\n", elapsed)

        // Check some condition
        if elapsed > 2*time.Second {
            fmt.Println("Task is progressing normally")
        } else {
            fmt.Println("Task might be running slowly")
        }
    }, 3)

    // Keep the program running
    fmt.Println("Waiting for the check...")
    time.Sleep(5 * time.Second)
}

Installation

go get oss.nandlabs.io/golly/fnutils

Error Utilities File System Utilities