Quick Answer
In Rust, backticks have several syntactic meanings:
According to the documentation[1], backticks are used to refer to names or combinations of symbols that are otherwise reserved or illegal. For example, keywords in Rust like if cannot be used directly as variable names, so backticks allow them to be used.
Lifetime parameters in Rust generics must start with a single apostrophe ' to denote they are lifetime parameters[2]. For example, 'a is a common lifetime parameter name.
Backticks are also used in struct field tags in Go[3]. The content inside backticks in struct field definitions in Go become attributes of those fields.
The Rust reference documentation also describes backticks[4][5]. Backticks enclose tokens in Rust. Tokens are the basic elements that make up Rust code and are broken down by the compiler. Specifically, backticks are used to denote operator tokens like +, -, etc. They also enclose pattern matches in match expressions joined with the | operator.
In shell commands, backticks were historically used for command substitution, running the command inside the backticks and substituting its output into the command line[6]. However, this usage is now discouraged and $(command) is preferred.
So in summary, in Rust backticks have several syntactic meanings - to allow otherwise reserved names to be used, to denote lifetime parameters, to enclose operators and pattern matches, and historically in shell commands for command substitution.
What do backticks do in R? - Stack Overflow
rust - What are the identifiers denoted with a single apostrophe ...
go - What is the usage of backtick in golang structs definition ...
B - Operators and Symbols - The Rust Programming Language
Tokens - The Rust Reference
shell - What does ` (backquote/backtick) mean in commands? - Unix ...
