Crate v_escape provides a macro, new_escape! that define a struct with escaping functionality. These macros are optimized using simd by default, but this can be alter using sub-attributes.

Quick start

In order to use v_escape you will have to call one of the two macros to create a escape struct. In this example, when using the macro new_escape!(MyEscape, "62->bar"); a new a struct MyEscape will be created that every time its method MyEscape::fmt is called will replace all characters ">" with "bar".

#[macro_use]
extern crate v_escape;

new_escape!(MyEscape, "62->bar");

# fn main() {
# let s = "foo>bar";
let escaped = escape(s);

print!("{}", escaped);
# }

Pairs syntax

v_escape uses a simple syntax to replace characters with their respective quotes. The tuple is named Pair, and several can be defined, referred as Pairs. The syntax to define Pairs consists of a character, followed by the delimiter ->, followed by the substitution quote and the delimiter || (last delimiter is optional):

([character]->[quote] || )*

• character : Character to substitute. Acceptsi8+ from 0 to i8::MAX and accepts the following formats: decimal (49), hexadecimal (0x31), octal (0o61) or character (#1). Note: Numbers are read in ASCII: #6->foo

• quote : Characters that will replace character

# #[macro_use]
# extern crate v_escape;
new_escape!(MyEscape, "49->bar");
# fn main() {
assert_eq!(escape("foo 1").to_string(), "foo bar");
# }

# #[macro_use]
# extern crate v_escape;
new_escape!(MyEscape, "0x31->bar");
# fn main() {
assert_eq!(escape("foo 1").to_string(), "foo bar");
# }

# #[macro_use]
# extern crate v_escape;
new_escape!(MyEscape, "0o61->bar");
# fn main() {
assert_eq!(escape("foo 1").to_string(), "foo bar");
# }

# #[macro_use]
# extern crate v_escape;
new_escape!(MyEscape, "#1->bar");
# fn main() {
assert_eq!(escape("foo 1").to_string(), "foo bar");
# }

In the following example more than 16 pairs are given, this exceeds simd's boundary. If simd optimization is wanted, ranges must be enabled (default) or an error will be thrown. It is possible to not use ranges but simd optimization has to be disabled.

# #[macro_use]
# extern crate v_escape;
new_escape!(
MyEscape,
"62->b || 60->f || B->b || 65->f || 0o67->b || #6->f || 68->b || \
71->f || 72->b || 73->f || 74->b || 75->f || 76->b || 77->f || \
78->b || 79->f || 0x1A->f"
);
# fn main() {
assert_eq!(escape("foo>bar<").to_string(), "foobbarf");
# }

For debugging purposes, sub-attribute print, can be set to true to print generated code

# #[macro_use]
# extern crate v_escape;
new_escape!(MyEscape, "o->bar", print = true);
# fn main() {
# assert_eq!(escape("foo").to_string(), "fbarbar");
# }