docs: format annotation (#62)

README.md

@@ -1,4 +1,5 @@
 # go-quartz
+
 [![Build](https://github.com/reugn/go-quartz/actions/workflows/build.yml/badge.svg)](https://github.com/reugn/go-quartz/actions/workflows/build.yml)
 [![PkgGoDev](https://pkg.go.dev/badge/github.com/reugn/go-quartz)](https://pkg.go.dev/github.com/reugn/go-quartz)
 [![Go Report Card](https://goreportcard.com/badge/github.com/reugn/go-quartz)](https://goreportcard.com/report/github.com/reugn/go-quartz)
@@ -7,71 +8,96 @@
 A minimalistic and zero-dependency scheduling library for Go.
 
 ## About
+
 Inspired by the [Quartz](https://github.com/quartz-scheduler/quartz) Java scheduler.
 
 ### Library building blocks
-Scheduler interface
+
+#### Scheduler interface
+
 ```go
 type Scheduler interface {
 	// Start starts the scheduler. The scheduler will run until
 	// the Stop method is called or the context is canceled. Use
 	// the Wait method to block until all running jobs have completed.
 	Start(context.Context)
+
 	// IsStarted determines whether the scheduler has been started.
 	IsStarted() bool
+
 	// ScheduleJob schedules a job using a specified trigger.
 	ScheduleJob(ctx context.Context, job Job, trigger Trigger) error
+
 	// GetJobKeys returns the keys of all of the scheduled jobs.
 	GetJobKeys() []int
+
 	// GetScheduledJob returns the scheduled job with the specified key.
 	GetScheduledJob(key int) (*ScheduledJob, error)
+
 	// DeleteJob removes the job with the specified key from the Scheduler's execution queue.
 	DeleteJob(key int) error
+
 	// Clear removes all of the scheduled jobs.
 	Clear()
+
 	// Stop shutdowns the scheduler.
 	Stop()
+
 	// Wait blocks until the scheduler stops running and all jobs
 	// have returned. Wait will return when the context passed to
 	// it has expired. Until the context passed to start is
 	// cancelled or Stop is called directly.
 	Wait(context.Context)
 }
 ```
+
 Implemented Schedulers
+
 - StdScheduler
 
-Trigger interface
+#### Trigger interface
+
 ```go
 type Trigger interface {
 	// NextFireTime returns the next time at which the Trigger is scheduled to fire.
 	NextFireTime(prev int64) (int64, error)
+
 	// Description returns the description of the Trigger.
 	Description() string
 }
 ```
+
 Implemented Triggers
+
 - CronTrigger
 - SimpleTrigger
 - RunOnceTrigger
 
-Job interface. Any type that implements it can be scheduled.
+#### Job interface
+
+Any type that implements it can be scheduled.
+
 ```go
 type Job interface {
 	// Execute is called by a Scheduler when the Trigger associated with this job fires.
 	Execute(context.Context)
+
 	// Description returns the description of the Job.
 	Description() string
+
 	// Key returns the unique key for the Job.
 	Key() int
 }
 ```
+
 Implemented Jobs
+
 - ShellJob
 - CurlJob
 - FunctionJob
 
 ## Cron expression format
+
 | Field Name   | Mandatory | Allowed Values  | Allowed Special Characters |
 | ------------ | --------- | --------------- | -------------------------- |
 | Seconds      | YES       | 0-59            | , - * /                    |
@@ -83,22 +109,52 @@ Implemented Jobs
 | Year         | NO        | empty, 1970-    | , - * /                    |
 
 ## Examples
+
 ```go
-ctx := context.Background()
-sched := quartz.NewStdScheduler()
-sched.Start(ctx)
-cronTrigger, _ := quartz.NewCronTrigger("1/5 * * * * *")
-shellJob := quartz.NewShellJob("ls -la")
-request, _ := http.NewRequest(http.MethodGet, "https://worldtimeapi.org/api/timezone/utc", nil)
-curlJob, _ := quartz.NewCurlJob(request)
-functionJob := quartz.NewFunctionJob(func(_ context.Context) (int, error) { return 42, nil })
-sched.ScheduleJob(shellJob, cronTrigger)
-sched.ScheduleJob(curlJob, quartz.NewSimpleTrigger(time.Second*7))
-sched.ScheduleJob(functionJob, quartz.NewSimpleTrigger(time.Second*5))
-sched.Stop()
-sched.Wait(ctx)
+package main
+
+import (
+	"context"
+	"net/http"
+	"time"
+
+	"github.com/reugn/go-quartz/quartz"
+)
+
+func main() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// create scheduler
+	sched := quartz.NewStdScheduler()
+
+	// async start scheduler
+	sched.Start(ctx)
+
+	// create jobs
+	cronTrigger, _ := quartz.NewCronTrigger("1/5 * * * * *")
+	shellJob := quartz.NewShellJob("ls -la")
+
+	request, _ := http.NewRequest(http.MethodGet, "https://worldtimeapi.org/api/timezone/utc", nil)
+	curlJob, _ := quartz.NewCurlJob(request)
+
+	functionJob := quartz.NewFunctionJob(func(_ context.Context) (int, error) { return 42, nil })
+
+	// register jobs to scheduler
+	sched.ScheduleJob(ctx, shellJob, cronTrigger)
+	sched.ScheduleJob(ctx, curlJob, quartz.NewSimpleTrigger(time.Second*7))
+	sched.ScheduleJob(ctx, functionJob, quartz.NewSimpleTrigger(time.Second*5))
+
+	// stop scheduler
+	sched.Stop()
+
+	// wait for all workers to exit
+	sched.Wait(ctx)
+}
 ```
+
 More code samples can be found in the examples directory.
 
 ## License
+
 Licensed under the MIT License.