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Reference
Reference is an esolang invented by User:None1 that can read its source code, but not modify it.
Commands
| Command | Meaning | Example |
|---|---|---|
| [i~j] (i,j are positive decimal integers) | Output the i-th to the j-th characters of the source code | [3~5] prints the third to the fifth characters of the source code
|
| \ | Escape character | \x prints x.
|
| Other characters | Print themselves | a prints a
|
When the parser sees a [, it tries to find the nearest ], if there is no nearest ] or the things between the two brackets do not follow the [i~j] format, the [ is treated as Other characters.
Files in Windows use CR+LF as newlines, to avoid this issue, an interpreter removes all CR characters in the source code read before interpreting it.
Examples
Hello, World!
Hello, World!
Quine
Quine
Another Quine (cheating)
[1~5]
Output [
\[
Output ]
]
Truth-machine
Only works if it supports nested reference (interpret the selected characters), and input 0 prints 0[0~6.
[11~2x]____[5~5][0~6]
x is the input.