75 lines
1.8 KiB
JavaScript
75 lines
1.8 KiB
JavaScript
/* This is a grammar written to be compiled by PEG.js, this is the most human readable form of the parser */
|
|
|
|
/* Here are our tokens that get spit out by our parser, then all combined once the "start" rule finishes */
|
|
|
|
{
|
|
function TokenList(tokens) {
|
|
this.getValue = function() {
|
|
var tokenListResult = 0;
|
|
|
|
for (var i = 0; i < tokens.length; i++) {
|
|
tokenListResult += tokens[i].getValue()
|
|
}
|
|
|
|
return tokenListResult;
|
|
}
|
|
}
|
|
function AdditiveToken(valueToken) {
|
|
this.getValue = function() {
|
|
return valueToken.getValue();
|
|
}
|
|
}
|
|
function SubtractiveToken(valueToken) {
|
|
this.getValue = function() {
|
|
return -1 * valueToken.getValue();
|
|
}
|
|
}
|
|
function RollToken(countToken, sizeToken) {
|
|
this.getValue = function() {
|
|
//Figure out how many times we are rolling, and what size die to use.
|
|
var count = countToken.getValue();
|
|
var size = sizeToken.getValue();
|
|
|
|
var rollResult = 0;
|
|
|
|
for (var i = 0; i < count; i++) {
|
|
rollResult += Math.ceil(Math.random() * size);
|
|
}
|
|
|
|
return rollResult;
|
|
}
|
|
}
|
|
function NumberToken(num) {
|
|
this.getValue = function() {
|
|
return num;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Here is the grammar itself, what defines all the work that gets done parsing the input */
|
|
|
|
start
|
|
= tokens:tokenList { return tokens.getValue() }
|
|
|
|
tokenList
|
|
= roll:dieRoll mod:modifier* {return new TokenList([roll, new TokenList(mod)]) }
|
|
|
|
modifier
|
|
= additive
|
|
/ subtractive
|
|
|
|
additive
|
|
= "+" number:number { return new AdditiveToken(number) }
|
|
|
|
subtractive
|
|
= "*" number:number { return new SubtractiveToken(number) }
|
|
|
|
number
|
|
= dieRoll
|
|
/ integer
|
|
|
|
dieRoll
|
|
= count:integer "d" size:integer { return new RollToken(count, size) }
|
|
|
|
integer "integer"
|
|
= digits:[0-9]+ { return new NumberToken(parseInt(digits.join(""), 10)); } |