Mercurial Hosting > luan
diff core/src/luan/modules/parsers/ParseException.java @ 585:bb3818249dfb
add Parsers
author | Franklin Schmidt <fschmidt@gmail.com> |
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date | Fri, 14 Aug 2015 06:35:20 -0600 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/core/src/luan/modules/parsers/ParseException.java Fri Aug 14 06:35:20 2015 -0600 @@ -0,0 +1,51 @@ +package luan.modules.parsers; + + +public final class ParseException extends Exception { + public final String text; + public final int errorIndex; + public final int highIndex; + + ParseException(Parser parser,String msg) { + super(msg); + this.text = parser.text; + this.errorIndex = parser.currentIndex(); + this.highIndex = parser.highIndex(); + } + + private class Location { + final int line; + final int pos; + + Location(int index) { + int line = 0; + int i = -1; + while(true) { + int j = text.indexOf('\n',i+1); + if( j == -1 || j >= index ) + break; + i = j; + line++; + } + this.line = line; + this.pos = index - i - 1; + } + } + + private String[] lines() { + return text.split("\n",-1); + } + + @Override public String getMessage() { + Location loc = new Location(errorIndex); + String line = lines()[loc.line]; + String msg = super.getMessage() + " (line " + (loc.line+1) + ", pos " + (loc.pos+1) + ")\n"; + StringBuilder sb = new StringBuilder(msg); + sb.append( line + "\n" ); + for( int i=0; i<loc.pos; i++ ) { + sb.append( line.charAt(i)=='\t' ? '\t' : ' ' ); + } + sb.append("^\n"); + return sb.toString(); + } +}