gosexy/to

Convenient functions for converting values between common Go datatypes.

What if, instead of producing errors because your (human) user did not feed correctly formatted data into your program, you try to make your code get over it and keep going? Remember that, for any sane human, the string "5" is exactly the same thing as the uint 5 (or was it a uint64?) and a number could be "12.34", even if your program expects only integers.

Life is too short for properly catching trivial conversion errors and for bothering users with silly computer details, such as the difference between "123" and 123.

This package allows quick conversions between Go datatypes, when any conversion seems unreasonable, a zero value of the expected type is always guaranteed.

Please be aware that this package does not consider conversion errors to be important enough to be returned or handled, if some conversion error happens it instead returns the zero value with no additional drama. If you're not working with human provided data, fuzzy input or if you prefer not to ignore any error in your program, you'd better use the standard Go packages for conversion, such as strconv or even fmt, they may be better suited for the task.

Installation

go get -u menteslibres.net/gosexy/to

Usage

Import the package

import "menteslibres.net/gosexy/to"

Use the available to functions to convert a float64 into a string:

// "1.23"
s := to.String(1.23)

Or a bool into string:

// "true"
s := to.String(true)

What about the other way around? string to float64 and string to bool.

// 1.23
f := to.Float64("1.23")

// true
b := to.Bool("true")

Note that this package only provides to.Uint64(), to.Int64() and to.Float64() but no to.Uint8(), to.Uint() or to.Float32() functions, if you'd like to produce a float32 instead of a float64 you'd first use to.Float64() and then cast the output using float32().

f32 := float32(to.Float64("12.34"))

There is another important function, to.Convert() that accepts any value (interface{}) as first argument and also a reflect.Kind, as second, that defines the data type the first argument will be converted to, this is also the only function that returns an error value.

val, err := to.Convert("12345", reflect.Int64)

Date formats and durations are also handled, you can use many fuzzy date formats and they would be converted into time.Time values.

timeVal = to.Time("2012-03-24")
timeVal = to.Time("Mar 24, 2012")

durationVal := to.Duration("12s37ms")

Now, an important question: how fast is this library compared to standard methods, like the fmt or strconv packages?

It is, of course, a little slower that strconv methods but it is faster than fmt, so it provides an acceptable speed for most projects. You can test it by yourself:

$ go test -test.bench=.
PASS
BenchmarkFmtIntToString           5000000               547 ns/op
BenchmarkFmtFloatToString         2000000               914 ns/op
BenchmarkStrconvIntToString      10000000               142 ns/op
BenchmarkStrconvFloatToString     1000000              1155 ns/op
BenchmarkIntToString             10000000               325 ns/op
BenchmarkFloatToString            2000000               873 ns/op
BenchmarkIntToBytes              10000000               198 ns/op
BenchmarkBoolToString            50000000                48.0 ns/op
BenchmarkFloatToBytes             2000000               773 ns/op
BenchmarkIntToBool                5000000               403 ns/op
BenchmarkStringToTime             1000000              1063 ns/op
BenchmarkConvert                 10000000               199 ns/op
ok      menteslibres.net/gosexy/to      27.670s

See the docs for a full reference of all the available to methods.

License

This is Open Source released under the terms of the MIT License:

Copyright (c) 2013 José Carlos Nieto, https://menteslibres.net/xiam

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.