DebugPrint

A Flutter-inspired, debug-only logger for Android, written in Kotlin.

DebugPrint gives you a familiar debugPrint.d("hello") API, auto-detects debug builds, auto-tags logs with File.fn:line, and stays completely silent in release.

Features

• 🎯 Flutter-style API — debugPrint.d("msg"), dprint.e("Tag", "oops"), dlog.w { ... }
• 🔇 Silent in release — auto-enabled in debug, auto-disabled in release
• ⚙️ Zero config — no init() call, no Application setup, no BuildConfig wiring
• 📍 Auto tag — File.function:line derived from the caller (toggleable)
• 🧵 Lazy messages — debugPrint.d { "expensive $x" } never builds the string when disabled
• 🎚️ Log levels — .v .d .i .w .e
• 🏷️ Custom tags — debugPrint.d("Auth", "token expired")
• 🔌 Pluggable sinks — swap Logcat for file / Crashlytics / remote
• 🛡️ Never crashes — logging errors are swallowed silently
• 📦 Tiny — pure Kotlin, one small AAR

Installation

implementation("com.flagodna:debugprint:0.1.1")

Usage

Basic

import com.flagodna.debugprint.debugPrint

debugPrint.d("Hello from debugPrint!")
debugPrint.i("User signed in")
debugPrint.w("Cache miss")
debugPrint.e("Payment failed")
debugPrint.v("Verbose detail")

With a custom tag

debugPrint.d("Auth", "token about to expire")
debugPrint.e("Payments", "charge declined")

Lazy messages

Use the lambda overload for anything expensive:

debugPrint.d { "user = $user, size = ${bigList.size}" }

The string is only built if logging is enabled.

Aliases

All three names point to the same object:

debugPrint.d("short")
dprint.d("shorter")
dlog.d("shortest")

Levels

Method	Logcat level
.v	VERBOSE
.d	DEBUG
.i	INFO
.w	WARN
.e	ERROR

Each level supports:

debugPrint.d("message")           // auto tag
debugPrint.d("Tag", "message")    // custom tag
debugPrint.d { "message" }        // lazy

Behavior

Build type	DebugPrint.enabled	Output
Debug	true (auto)	Logcat
Release	false (auto)	(nothing)

The enabled flag is set once, automatically, before Application.onCreate() runs. No setup in your Application class is required.

Custom sinks

Implement DebugPrintSink to route logs anywhere:

import com.flagodna.debugprint.DebugPrintSink

class FileSink(private val file: File) : DebugPrintSink {
    override fun print(level: Int, tag: String, message: String) {
        file.appendText("[$level] $tag: $message\n")
    }
}

DebugPrint.sink = FileSink(File(context.filesDir, "app.log"))

A sink must never throw — DebugPrint swallows any exception from a sink.

Performance notes

• Non-lambda calls — debugPrint.d("msg") is a field read + a branch when disabled.
• Lambda calls — debugPrint.d { "msg" } skips string construction entirely when disabled.
• Auto-tag — costs a stack walk per call. Disable for hot loops:

DebugPrint.autoTag = false
for (i in 1..100_000) debugPrint.d("iteration $i")  // fast, tag = defaultTag
DebugPrint.autoTag = true

Or pass a custom tag, which also skips the stack walk:

for (i in 1..100_000) debugPrint.d("Loop", "iteration $i")