00001 /******************************************************************************* 00002 00003 @file TextWriter.d 00004 00005 Copyright (c) 2004 Kris Bell 00006 00007 This software is provided 'as-is', without any express or implied 00008 warranty. In no event will the authors be held liable for damages 00009 of any kind arising from the use of this software. 00010 00011 Permission is hereby granted to anyone to use this software for any 00012 purpose, including commercial applications, and to alter it and/or 00013 redistribute it freely, subject to the following restrictions: 00014 00015 1. The origin of this software must not be misrepresented; you must 00016 not claim that you wrote the original software. If you use this 00017 software in a product, an acknowledgment within documentation of 00018 said product would be appreciated but is not required. 00019 00020 2. Altered source versions must be plainly marked as such, and must 00021 not be misrepresented as being the original software. 00022 00023 3. This notice may not be removed or altered from any distribution 00024 of the source. 00025 00026 4. Derivative works are permitted, but they must carry this notice 00027 in full and credit the original source. 00028 00029 00030 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 00031 00032 00033 @version Initial version, March 2004 00034 @author Kris 00035 00036 00037 *******************************************************************************/ 00038 00039 module mango.io.TextWriter; 00040 00041 public import mango.io.DisplayWriter; 00042 00043 /******************************************************************************* 00044 00045 Print readable output to an IWriter seperated by delimiters. Note 00046 that the delimiter should be chosen such that it doesn't conflict 00047 with any other characters being written. For example, by choosing 00048 a comma-delimiter, you should ensure a comma is not output within 00049 a text string (so the output can be easily tokenized when read). 00050 00051 *******************************************************************************/ 00052 00053 class TextWriter : DisplayWriter 00054 { 00055 private byte ignore; 00056 private char[] delimiter; 00057 00058 alias opShl put; 00059 alias DisplayWriter.opShl opShl; 00060 00061 /*********************************************************************** 00062 00063 Construct a TextWriter using the provided buffer. Output 00064 is seperated with the given delimiter string. 00065 00066 ***********************************************************************/ 00067 00068 this (IBuffer buffer, char[] delimiter) 00069 { 00070 super (buffer); 00071 this.delimiter = delimiter; 00072 } 00073 00074 /*********************************************************************** 00075 00076 Reset this writer, so it won't emit the specified series 00077 of subsequent delimeters 00078 00079 ***********************************************************************/ 00080 00081 void suppress (byte count) 00082 { 00083 ignore += count; 00084 } 00085 00086 /*********************************************************************** 00087 00088 Intercept the IWritable method to catch newlines 00089 00090 ***********************************************************************/ 00091 00092 override IWriter opShl (IWritable x) 00093 { 00094 // don't delimit writable if it's to be ignored 00095 if (cast(IPhantomWriter) x) 00096 suppress (1); 00097 00098 // have superclass print the IWritable 00099 return super.opShl (x); 00100 } 00101 00102 /*********************************************************************** 00103 00104 Intercept the output so we can append a delimiter. 00105 00106 ***********************************************************************/ 00107 00108 override IWriter opShl (char[] x) 00109 { 00110 super.opShl (x); 00111 return delimit (); 00112 } 00113 00114 /*********************************************************************** 00115 00116 Intercept the output so we can append a delimiter. 00117 00118 ***********************************************************************/ 00119 00120 override IWriter opShlw (wchar[] x) 00121 { 00122 super.opShlw (x); 00123 return delimit (); 00124 } 00125 00126 /*********************************************************************** 00127 00128 Intercept the output so we can append a delimiter. 00129 00130 ***********************************************************************/ 00131 00132 override IWriter opShld (dchar[] x) 00133 { 00134 super.opShld (x); 00135 return delimit (); 00136 } 00137 00138 /*********************************************************************** 00139 00140 write a delimiter after each token 00141 00142 ***********************************************************************/ 00143 00144 private final IWriter delimit () 00145 { 00146 // output the delimiter? 00147 if (ignore) 00148 --ignore; 00149 else 00150 encode.char8 (delimiter, delimiter.length); 00151 return this; 00152 } 00153 }