AleoHQ/leo
1
1
Fork 0
mirror of https://github.com/AleoHQ/leo.git synced 2025-01-03 07:16:50 +03:00
Code Issues Packages Projects Releases Wiki Activity

Disallow underbars in \u{} escapes.

Browse Source 
Rust allows `\u{1_____0__F____F______FF__________________________}` to mean `\u{10FFFF}`, in both char and string literals.  This PR, if accepted, would disallow this syntax in Leo char and string literals.
This commit is contained in:
Eric McCarthy 2021-06-06 20:10:06 -07:00 committed by GitHub
parent e1b59a283c
commit b59b77df30
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
docs/rfc/001-initial-strings.md
View File

@ -100,8 +100,11 @@ Both uppercase and lowercase letters are allowed.
The `u` must be lowercase.
The value must be between 0 and 10FFFF, inclusive.
Note that this syntax for character literals is identical to the Rust syntax documented here (as of 2021-05-26):
Note that this syntax for character literals is very close to the Rust syntax documented here (as of 2021-05-26):
https://doc.rust-lang.org/reference/tokens.html#character-literals
The only difference is that this syntax does not support Unicode escapes with underbars in them.
The following is true in Rust but not in this proposal for Leo:
`'\u{1_____0__F____F______FF__________________________}' == '\u{10FFFF}'`.
Note that the literal character is assembled by the compiler---for
creating literals, there is no need for the circuit to know
@ -178,11 +181,12 @@ https://doc.rust-lang.org/reference/tokens.html#string-literals.
The main difference is that this syntax does not support the Rust `STRING_CONTINUE` syntax.
In this syntax a backslash may not be followed by a newline, and newlines have no special handling.
Another differences is that this syntax does **not** permit the empty string `""`.
Also, this syntax does not allow underbars in Unicode escapes in string literals.
The type of a string literal is `[char; N]`,
where `N` is the length of the string measured in characters,
i.e. the size of the array.
Note that there is no notion of Unicode encoding (e.g. UTF-8)
Note that in this language design there is no notion of Unicode encoding (e.g. UTF-8)
that applies to string literals.
The rationale for not introducing a new type for strings initially,