1//===--- NumericLiteralInfo.cpp ---------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8///
9/// \file
10/// This file implements the functionality of getting information about a
11/// numeric literal string, including 0-based positions of the base letter, the
12/// decimal/hexadecimal point, the exponent letter, and the suffix, or npos if
13/// absent.
14///
15//===----------------------------------------------------------------------===//
16
17#include "NumericLiteralInfo.h"
18#include "llvm/ADT/StringExtras.h"
19
20namespace clang {
21namespace format {
22
23using namespace llvm;
24
25NumericLiteralInfo::NumericLiteralInfo(StringRef Text, char Separator) {
26 if (Text.size() < 2)
27 return;
28
29 bool IsHex = false;
30 if (Text[0] == '0') {
31 switch (Text[1]) {
32 case 'x':
33 case 'X':
34 IsHex = true;
35 [[fallthrough]];
36 case 'b':
37 case 'B':
38 case 'o': // JavaScript octal.
39 case 'O':
40 BaseLetterPos = 1; // e.g. 0xF
41 break;
42 }
43 }
44
45 DotPos = Text.find(C: '.', From: BaseLetterPos + 1); // e.g. 0x.1 or .1
46
47 // e.g. 1.e2 or 0xFp2
48 const auto Pos = DotPos != StringRef::npos ? DotPos + 1 : BaseLetterPos + 2;
49
50 ExponentLetterPos =
51 // Trim C++ user-defined suffix as in `1_Pa`.
52 (Separator == '\'' ? Text.take_front(N: Text.find(C: '_')) : Text)
53 .find_insensitive(C: IsHex ? 'p' : 'e', From: Pos);
54
55 const bool HasExponent = ExponentLetterPos != StringRef::npos;
56 SuffixPos = Text.find_if_not(
57 F: [&](char C) {
58 return (HasExponent || !IsHex ? isDigit : isHexDigit)(C) ||
59 C == Separator;
60 },
61 From: HasExponent ? ExponentLetterPos + 2 : Pos); // e.g. 1e-2f
62}
63
64} // namespace format
65} // namespace clang
66