Tutorial

Preface

Human2Regex (H2R) is a way to spell out a regular expression in an easy to read, easy to modify language. H2R supports multiple languages as well as many (though not all) different regular expression options such as named groups and quantifiers. You may notice multiple keywords specifying the same thing, and that is intended! H2R is made to be flexible and easy to understand. With a range, do you prefer "...", "through", or "to"? It's up to you to choose, H2R supports all of those!

Your first Match

Every language starts with a "Hello World" program, so let's match the output of those programs. Matching is done using the keyword "match" followed by what you want to match. match "Hello World" The above statement will generate a regular expression that matches "Hello World". Any invalid characters will automatically be escaped, so you don't need to worry about it. H2R also supports block comments with /**/, or line comments with // or # so you can explain why or what you intend to match. match "Hello World" // matches the output of "Hello World" programs Now what if we want to match every case variation of "Hello World" like "hello world" or "hELLO wORLD"? H2R supports the or operator which allows you to specify many possible combinations. match "Hello World" or "hello world" or "hELLO wORLD" Or, you can use a using statement to specify that you want it to be case insensitive.

Using Specifiers

Using statements appear at the beginning. You may have one or more using statements which each can contain one or more specifiers. For example: using global and case insensitive matching or using global using case insensitive The matching keyword is optional. The flags which are available are:

To match any variation of hello world, we would then do the following: using case insensitive matching match "hello world"

Matching multiple items

H2R comes with 2 options to match multiple items in a row. The first is to simply write multiple seperate match statements like: match "hello" match " " match "world" However, you can also use a comma, and, or then for a more concise match. match "hello", " ", "world" or match "hello" and " " and "world" or match "hello" then " " then "world" or any combination like match "hello", " " and then "world"

Optionality

Sometimes you wish to match something that may or may not exist. In H2R, this is done via the optional or optionally keyword. optionally match "hello world" will match 0 or 1 "hello world"'s. This can be used along side matching multiple statements in a single match statement. match "hello", optionally " ", "world" will match "hello", an optional space if it exists, and "world". However, the start optional is for the entire match statement. Thus, optionally match "hello", " ", then "world" will actually make the whole "hello world" an optional match rather than just the first "hello". If you want to make the first match optional but keep the rest required, use multiple match statements.

Negation

You can negate a match with the operator not match not "hello world" will match everything except for "hello world".

Other matching specifiers

Many times you don't know exactly what you wish to match. H2R comes with many specifiers that you can use for your matching. For example, you may wish to match any word. You can do that with: match a word The a or an is optional. The possible specifiers that H2R supports are the following:

You can also create ranges of characters to match. Say for example, you wanted to match any characters between a and z, you could write any of the following: match from "a" to "z" // from is optional or match between "a" and "z" // between is optional or match "a" ... "z" // can use ... or .. or match "a" - "z" or match "a" through "z" // can also use thru

Repetition

TODO

Grouping

TODO

Miscellaneous features

Unicode character properties

You can match specific unicode sequences using "\uXXXX" or "\UXXXXXXXX" where X is a hexadecimal character. match "\u0669" // matches arabic digit 9 "٩" Unicode character classes/scripts can be matched using the unicode keyword. match unicode "Latin" // matches any latin character match unicode "N" // matches any number character The following Unicode class specifiers are available:

The following Unicode script specifiers are available:

Note: Java and .NET require "Is" in front of the script name. For example, "IsLatin" rather than just "Latin"