Wiki: easygen is not only for cli but it's a Universal code/text generator

[suntong]

Here is easygen using the same YAML file of:

easygen/cmd/easygen/easygen.yaml

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	# program name, name for the executable
	ProgramName: easygen
	# package name
	# - For standalone program that does not belong to any package, e.g.,
	# https://github.com/suntong/easygen/blob/7791e4f0e5605543d27da1671a21376cdb9dcf2a/easygen/easygen.go
	# just ignore the first line, the `package` output, and copy the rest
	# - If you don't mind using a separated file to handle commandline paramters,
	# then name the package as "main". see the spin-out "TF-minus1.go" file under
	# https://github.com/suntong/easygen/tree/d1ab0b5fe80ddac57fe9ef51f6ccb3ab998cd5ee
	# - If you are using it in a pacakge, look no further than
	# https://github.com/suntong/easygen/blob/master/easygenapi/config.go
	# which was a direct dump: easygen test/commandlineFlag | gofmt > easygenapi/config.go
	#
	PackageName: easygen
	# Name of the structure to hold the values for/from commandline
	StructName: Options
	# The actual variable that hold the commandline paramter values
	StructVar: Opts
	Options:
	- Name: TemplateStr
	Type: string
	Flag: ts
	Value: '""'
	Usage: "template string (in text)"
	- Name: ExtYaml
	Type: string
	Flag: ey
	Value: '".yaml"'
	Usage: "`extension` of yaml file"
	- Name: ExtJson
	Type: string
	Flag: ej
	Value: '".json"'
	Usage: "`extension` of json file"
	- Name: ExtTmpl
	Type: string
	Flag: et
	Value: '".tmpl"'
	Usage: "`extension` of template file"
	- Name: Debug
	Type: int
	Flag: debug
	Value: 0
	Usage: "debugging `level`"
	# Whether to use the USAGE_SUMMARY in Usage help
	UsageSummary: ""
	UsageLead: "\\nUsage:\\n %s [flags] template_name [data_filename [data_filename...]]\\n\\nFlags:\\n\\n"
	UsageEnd: |
	template_name: The name for the template file.
	- Can have the extension (specified by -et) or without it.
	- Can include the path as well.
	- Can be a comma-separated list giving many template files, in which case
	at least one data_filename must be given.
	data_filename(s): The name for the .yaml or .json data.
	- If omitted derive from the template_name.
	- Can have the extension or without it. If withot extension,
	will try the .yaml file first then .json
	- Can include the path as well.
	- If there is a single data_filename, and it is "-",
	then read the data (.yaml or .json format) from stdin.
	Flag defaults can be overridden by corresponding environment variable, e.g.:
	EASYGEN_EY=.yml EASYGEN_ET=.tpl easygen ...

which is used to generates the cli code, and use it to auto-generate Go data structure instead:

easygen/config.go

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	// !!! !!!
	// WARNING: Code automatically generated. Editing discouraged.
	// !!! !!!
	package easygen
	////////////////////////////////////////////////////////////////////////////
	// Constant and data type/structure definitions
	const progname = "easygen" // os.Args[0]
	// The Options struct defines the structure to hold the commandline values
	type Options struct {
	TemplateStr string // template string (in text)
	ExtYaml string // `extension` of yaml file
	ExtJson string // `extension` of json file
	ExtTmpl string // `extension` of template file
	Debug int // debugging `level`
	}

from this template:

easygen/cmd/easygen/config.tmpl

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	// !!! !!!
	// WARNING: Code automatically generated. Editing discouraged.
	// !!! !!!
	package {{.PackageName}}
	////////////////////////////////////////////////////////////////////////////
	// Constant and data type/structure definitions
	const progname = "{{.ProgramName}}" // os.Args[0]
	// The {{.StructName}} struct defines the structure to hold the commandline values
	type {{.StructName}} struct { {{range .Options}}{{if ne .Name "SEPARATOR" }}
	{{.Name}} {{.Type}} // {{.Usage}}{{end}}{{end}}
	}

with this command:

easygen/cmd/easygen/easygen.gen.sh

Line 1 in cdf80e9

easygen config easygen | gofmt > ../../config.go

For more infomation, check out

EasyGen -- Universal code/text generator that is easy to use