grepr

README

Missing feature of the standard library: printing arbitrary inputs as Go code, with proper spacing and support for multi-line output with indentation. The name "repr" stands for "representation" and alludes to the Python function with the same name.

API doc: https://pkg.go.dev/github.com/mitranim/gg/grepr

Example:

package mock

import (
  "fmt"

  "github.com/mitranim/gg"
  "github.com/mitranim/gg/grepr"
)

type Outer struct {
  OuterId   int
  OuterName string
  Embed
  Inner *Inner
}

type Embed struct {
  EmbedId   int
  EmbedName string
}

type Inner struct {
  InnerId   *int
  InnerName *string
}

func main() {
  fmt.Println(grepr.String(Outer{
    OuterName: `outer`,
    Embed:     Embed{EmbedId: 20},
    Inner:     &Inner{
      InnerId:   gg.Ptr(30),
      InnerName: gg.Ptr(`inner`),
    },
  }))

  /**
  mock.Outer{
    OuterName: `outer`,
    Embed: mock.Embed{EmbedId: 20},
    Inner: &mock.Inner{
      InnerId: gg.Ptr(30),
      InnerName: gg.Ptr(`inner`),
    },
  }
  */
}

Documentation

Overview

Missing feature of the standard library: printing arbitrary inputs as Go code, with proper spacing and support for multi-line output with indentation. The name "repr" stands for "representation" and alludes to the Python function with the same name.

Index

• Variables
• func Bytes[A any](src A) []byte
• func BytesC[A any](conf Conf, src A) []byte
• func BytesIndent[A any](src A, lvl int) []byte
• func BytesIndentC[A any](conf Conf, src A, lvl int) []byte
• func Println[A any](src A)
• func PrintlnC[A any](conf Conf, src A)
• func Prn[A any](desc string, src A)
• func String[A any](src A) string
• func StringC[A any](conf Conf, src A) string
• func StringIndent[A any](src A, lvl int) string
• func StringIndentC[A any](conf Conf, src A, lvl int) string
• type Conf
  • func (self Conf) Fmt() Fmt
  • func (self Conf) IsMulti() bool
  • func (self Conf) IsSingle() bool
  • func (self Conf) SkipZeroFields() bool
• type Fmt

Examples

• String

Variables

var ConfDefault = Conf{Indent: gg.Indent}

Default config used by top-level formatting functions in this package.

var ConfFull = Conf{Indent: gg.Indent, ZeroFields: true}

Config that allows formatting of struct zero fields.

Functions

func Bytes

func Bytes[A any](src A) []byte

Similar to `fmt.Sprintf("%#v")` or `gg.GoString`, but more advanced. Formats the input as Go code, using the config `ConfDefault`, returning the resulting bytes.

func BytesC

func BytesC[A any](conf Conf, src A) []byte

Formats the input as Go code, using the given config, returning the resulting bytes.

func BytesIndent

func BytesIndent[A any](src A, lvl int) []byte

Formats the input as Go code, using the default config with the given indentation level, returning the resulting bytes.

func BytesIndentC

func BytesIndentC[A any](conf Conf, src A, lvl int) []byte

Formats the input as Go code, using the given config with the given indentation level, returning the resulting bytes.

func Println

func Println[A any](src A)

Shortcut for printing the input as Go code, using the default config.

func PrintlnC

func PrintlnC[A any](conf Conf, src A)

Shortcut for printing the input as Go code, using the given config.

func Prn

func Prn[A any](desc string, src A)

Shortcut for printing the input as Go code, prefixed with the given description, using the default config. Handy for debug-printing.

func String

func String[A any](src A) string

Similar to `fmt.Sprintf("%#v")` or `gg.GoString`, but more advanced. Formats the input as Go code, using the config `ConfDefault`, returning the resulting string.

Example

package main

import (
	"fmt"

	"github.com/mitranim/gg"
	"github.com/mitranim/gg/grepr"
)

type Outer struct {
	OuterId   int
	OuterName string
	Embed
	Inner *Inner
}

type Embed struct {
	EmbedId   int
	EmbedName string
}

type Inner struct {
	InnerId   *int
	InnerName *string
}

var testInner = Inner{
	InnerId:   gg.Ptr(30),
	InnerName: gg.Ptr(`inner`),
}

var testEmbed = Embed{EmbedId: 20}

var testOuter = Outer{
	OuterName: `outer`,
	Embed:     testEmbed,
	Inner:     &testInner,
}

func main() {
	fmt.Println(grepr.String(testOuter))
}

Output:

grepr_test.Outer{
    OuterName: `outer`,
    Embed: grepr_test.Embed{EmbedId: 20},
    Inner: &grepr_test.Inner{
        InnerId: gg.Ptr(30),
        InnerName: gg.Ptr(`inner`),
    },
}

func StringC

func StringC[A any](conf Conf, src A) string

Formats the input as Go code, using the given config, returning the resulting string.

func StringIndent

func StringIndent[A any](src A, lvl int) string

Formats the input as Go code, using the default config with the given indentation level, returning the resulting string.

func StringIndentC

func StringIndentC[A any](conf Conf, src A, lvl int) string

Formats the input as Go code, using the given config with the given indentation level, returning the resulting string.

Types

type Conf

type Conf struct {
	Indent     string
	ZeroFields bool
	Pkg        string
}

Formatting config.

• `.Indent` controls indentation. If empty, output is single line.
• `.ZeroFields`, if set, forces printing of zero fields in structs. By default zero fields are skipped.
• `.Pkg`, if set, indicates the package name to strip from type names.

func (Conf) Fmt

func (self Conf) Fmt() Fmt

Shortcut for creating a pretty-formatter with this config.

func (Conf) IsMulti

func (self Conf) IsMulti() bool

Short for "is multi line". Inverse of `.IsSingle`.

func (Conf) IsSingle

func (self Conf) IsSingle() bool

Short for "is single line". If `.Indent` is empty, this is true, and output is single-line. Otherwise output is multi-line.

func (Conf) SkipZeroFields

func (self Conf) SkipZeroFields() bool

Inverse of `.ZeroFields`.

type Fmt

type Fmt struct {
	Conf
	gg.Buf
	Lvl       int
	ElideType bool
	Visited   gg.Set[u.Pointer]
}

Short for "formatter".