zig/std/ascii.zig

229 lines
7.3 KiB
Zig

// Does NOT look at the locale the way C89's toupper(3), isspace() et cetera does.
// I could have taken only a u7 to make this clear, but it would be slower
// It is my opinion that encodings other than UTF-8 should not be supported.
//
// (and 128 bytes is not much to pay).
// Also does not handle Unicode character classes.
//
// https://upload.wikimedia.org/wikipedia/commons/thumb/c/cf/USASCII_code_chart.png/1200px-USASCII_code_chart.png
const tIndex = enum(u3) {
Alpha,
Hex,
Space,
Digit,
Lower,
Upper,
// Ctrl, < 0x20 || == DEL
// Print, = Graph || == ' '. NOT '\t' et cetera
Punct,
Graph,
//ASCII, | ~0b01111111
//isBlank, == ' ' || == '\x09'
};
const combinedTable = init: {
comptime var table: [256]u8 = undefined;
const std = @import("std");
const mem = std.mem;
const alpha = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,
};
const lower = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,
};
const upper = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
const digit = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
const hex = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
const space = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
const punct = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1,
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1,
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0,
};
const graph = [_]u1{
// 0, 1, 2, 3, 4, 5, 6, 7 ,8, 9,10,11,12,13,14,15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,
};
comptime var i = 0;
inline while (i < 128) : (i += 1) {
table[i] =
u8(alpha[i]) << @enumToInt(tIndex.Alpha) |
u8(hex[i]) << @enumToInt(tIndex.Hex) |
u8(space[i]) << @enumToInt(tIndex.Space) |
u8(digit[i]) << @enumToInt(tIndex.Digit) |
u8(lower[i]) << @enumToInt(tIndex.Lower) |
u8(upper[i]) << @enumToInt(tIndex.Upper) |
u8(punct[i]) << @enumToInt(tIndex.Punct) |
u8(graph[i]) << @enumToInt(tIndex.Graph);
}
mem.set(u8, table[128..256], 0);
break :init table;
};
fn inTable(c: u8, t: tIndex) bool {
return (combinedTable[c] & (u8(1) << @enumToInt(t))) != 0;
}
pub fn isAlNum(c: u8) bool {
return (combinedTable[c] & ((u8(1) << @enumToInt(tIndex.Alpha)) |
u8(1) << @enumToInt(tIndex.Digit))) != 0;
}
pub fn isAlpha(c: u8) bool {
return inTable(c, tIndex.Alpha);
}
pub fn isCntrl(c: u8) bool {
return c < 0x20 or c == 127; //DEL
}
pub fn isDigit(c: u8) bool {
return inTable(c, tIndex.Digit);
}
pub fn isGraph(c: u8) bool {
return inTable(c, tIndex.Graph);
}
pub fn isLower(c: u8) bool {
return inTable(c, tIndex.Lower);
}
pub fn isPrint(c: u8) bool {
return inTable(c, tIndex.Graph) or c == ' ';
}
pub fn isPunct(c: u8) bool {
return inTable(c, tIndex.Punct);
}
pub fn isSpace(c: u8) bool {
return inTable(c, tIndex.Space);
}
pub fn isUpper(c: u8) bool {
return inTable(c, tIndex.Upper);
}
pub fn isXDigit(c: u8) bool {
return inTable(c, tIndex.Hex);
}
pub fn isASCII(c: u8) bool {
return c < 128;
}
pub fn isBlank(c: u8) bool {
return (c == ' ') or (c == '\x09');
}
pub fn toUpper(c: u8) u8 {
if (isLower(c)) {
return c & 0b11011111;
} else {
return c;
}
}
pub fn toLower(c: u8) u8 {
if (isUpper(c)) {
return c | 0b00100000;
} else {
return c;
}
}
test "ascii character classes" {
const std = @import("std");
const testing = std.testing;
testing.expect('C' == toUpper('c'));
testing.expect(':' == toUpper(':'));
testing.expect('\xab' == toUpper('\xab'));
testing.expect('c' == toLower('C'));
testing.expect(isAlpha('c'));
testing.expect(!isAlpha('5'));
testing.expect(isSpace(' '));
}