Benchmarking good practices

Go is strong typed and object oriented by definition. To distinguish bad habits, benchmarking against the compiler performance is often convincing.

Logic

The most efficient loop is using a locally defined variable
Don't bother to use anything but the len() to get the size of an array
Don't duplicate code to handle the first item of a list
Don't try to keep a single exit
Always use shadowing inside a for loop even for a boolean.
Don't bother about irrelevant cases in a switch.
Use bit masking instead of a second if.
Get the bits representation of a byte using bits package is simple and efficient.

Math

math.Log2() is the most efficient to check that 2 is the sole divisor.

Arrays

Array of struct is as efficient as multiple arrays.
Array initialization using append is costly.
Using a method is marginally more efficient to add an element to an array.

Templates

Use implicit parsing for forms
Keep a global var to hold a template read from file

Buffers

No difference when writing to file
Returning a buffer as a string is marginally more expensive.
Package io is much more efficient than fmt which offers many more possibilities:
- write a simple string.
- write a buffer to a buffer.
When handling every byte of a buffer, use ReadByte.

Builder

No difference for a url builder between returning the string or the url.URL.