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README.md

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+# adhocore/gronx
+
+[![Latest Version](https://img.shields.io/github/release/adhocore/gronx.svg?style=flat-square)](https://github.com/adhocore/gronx/releases)
+[![Software License](https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square)](LICENSE)
+
+`gronx` is Golang cron expression parser ported from [adhocore/cron-expr](https://github.com/adhocore/php-cron-expr).
+
+- Zero dependency.
+- Very **fast** because it bails early in case a segment doesn't match.
+
+## Installation
+
+```sh
+go get -u github.com/adhocore/gronx
+```
+
+## Usage
+
+```go
+import (
+	"time"
+
+	"github.com/adhocore/gronx"
+)
+
+gron := gronx.New()
+expr := "* * * * *"
+
+// check if expr is due for current time
+gron.IsDue(expr)
+
+// check if expr is due for given time
+gron.IsDue(expr, time.Date(2021, time.April, 1, 1, 1, 0, 0, time.UTC))
+```
+
+---
+### Cron Expression
+
+Cron expression normally consists of 5 segments viz:
+```
+<minute> <hour> <day> <month> <weekday>
+```
+and sometimes there can be 6th segment for `<year>` at the end.
+
+### Real Abbreviations
+
+You can use real abbreviations for month and week days. eg: `JAN`, `dec`, `fri`, `SUN`
+
+### Tags
+
+Following tags are available and they are converted to real cron expressions before parsing:
+
+- *@yearly* or *@annually* - every year
+- *@monthly* - every month
+- *@daily* - every day
+- *@weekly* - every week
+- *@hourly* - every hour
+- *@5minutes* - every 5 minutes
+- *@10minutes* - every 10 minutes
+- *@15minutes* - every 15 minutes
+- *@30minutes* - every 30 minutes
+- *@always* - every minute
+
+```go
+gron.IsDue("@5minutes")
+```
+
+### Modifiers
+
+Following modifiers supported
+
+- *Day of Month / 3rd segment:*
+    - `L` stands for last day of month (eg: `L` could mean 29th for February in leap year)
+    - `W` stands for closest week day (eg: `10W` is closest week days (MON-FRI) to 10th date)
+- *Day of Week / 5th segment:*
+    - `L` stands for last weekday of month (eg: `2L` is last monday)
+    - `#` stands for nth day of week in the month (eg: `1#2` is second sunday)
+
+---
+## License
+
+> &copy; [MIT](./LICENSE) | 2017-2019, Jitendra Adhikari
+
+## Credits
+
+This project is ported from [adhocore/cron-expr](https://github.com/adhocore/php-cron-expr) and
+release managed by [please](https://github.com/adhocore/please).