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view examples/fc/fc4b.syn @ 6:607e3be6bad8
Adjust to the moving target called the C++ standard.
Apparently nowadays it's not allowed to define an explicit copy
constructor but not an assignment operator. Consequently, defining the
explicit copy constructor in terms of the implicit/automatic
assignment operator for general convenience no longer works.
Add assignment operators.
Caution: not tested with the IBM compiler, but there's no particular
reason it shouldn't work.
author | David A. Holland |
---|---|
date | Mon, 30 May 2022 23:46:22 -0400 |
parents | 13d2b8934445 |
children |
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/* AnaGram Programming Examples FC4B: Multiple Fahrenheit-Celsius conversion with signed numbers, floating point arithmetic, optional white space, and Kelvin temperature input. This grammar resolves the conflicts found in FC4. Copyright 1993 Parsifal Software. All Rights Reserved. This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software. Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions: 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. 3. This notice may not be removed or altered from any source distribution. */ [ test file mask = "*.fc4" // C1 traditional engine /* turn this off for production use */ // C2 default token type = double // C3 disregard white space // C4 lexeme {unsigned number, end of line} // C5 ] eof = -1 (void) grammar -> [temperature?, end of line]..., eof // P1 (void) temperature -> number:c, 'c' + 'C' ={ /* P2 */ double f = 9*c/5 + 32; printf("%.6g\370F = %.6g\370C = %.6g\370K\n",f,c,c+273.16); } -> number:f, 'f' + 'F' = { /* P3 */ double c = 5*(f-32)/9; printf("%.6g\370F = %.6g\370C = %.6g\370K\n",f,c,c+273.16); } -> '+'?, unsigned number:k, 'k' + 'K' ={ /* P3a */ double c = k - 273.16; double f = 9*c/5 + 32; printf("%.6g\370F = %.6g\370C = %.6g\370K\n", f, c, k); } -> error // P4 number -> '-', unsigned number:n =-n; // P5 -> '+'?, unsigned number:n =n; // P6 unsigned number -> integer, '.'? // P6a -> integer:i, '.', fraction:f =i+f; // P6b -> '.', fraction:f =f; // P6c integer -> '0-9':d =d-'0'; // P7 -> integer:n, '0-9':d =10*n+d-'0'; // P8 fraction -> '0-9':d =(d-'0')/10.; // P9 -> '0-9':d, fraction:f =(d-'0' + f)/10.; // P10 white space -> ' ' + '\t' // P11 -> "/*", ~eof?..., "*/" // P12 end of line -> ["//", ~(eof + '\n')?...], '\n' // P13