kopia lustrzana https://github.com/miklobit/TiddlyWiki5
304 wiersze
12 KiB
JavaScript
304 wiersze
12 KiB
JavaScript
/*\
|
|
title: $:/core/modules/wiki.filters.js
|
|
type: application/javascript
|
|
module-type: wikimethod
|
|
|
|
Adds tiddler filtering to the $tw.Wiki object.
|
|
|
|
TiddlyWiki has a special syntax for expressing filters. They can be used to select tiddlers for an operation, or to filter a set of tiddlers to add or remove members.
|
|
|
|
The mechanism is easiest to understand by first presenting some example filter strings:
|
|
|
|
|!Filter |!Results |
|
|
|`HelloThere` |The single tiddler titled `HelloThere` (if it exists) |
|
|
|`[[A Title With Several Words]]` |The single tiddler titled `A Title With Several Words` (if it exists) |
|
|
|`[title[MyTiddler]]` |The single tiddler titled `MyTiddler` (if it exists) |
|
|
|`HelloThere Introduction` |The tiddlers titled `HelloThere` and `Introduction` (if they exist) |
|
|
|`[tag[important]]` |Any tiddlers with the tag `important` |
|
|
|`[!tag[important]]` |Any tiddlers not with the tag `important` |
|
|
|`[tag[important]sort[title]]` |Any tiddlers with the tag `important` sorted by title |
|
|
|`[tag[important]!sort[title]]` |Any tiddlers with the tag `important` reverse sorted by title |
|
|
|`[[one][two][three]tag[tom]]` |Any of the tiddlers called `one`, `two` or `three` that exist and are tagged with `tom` |
|
|
|`[[one][two][three]] [tag[tom]]` |Any of the tiddlers called `one`, `two` or `three` that exist, along with all of the source tiddlers that are tagged with `tom` |
|
|
|`[tag[tom]] [tag[harry]] -[[one][two][three]]` |All tiddlers tagged either `tom` or `harry`, but excluding `one`, `two` and `three` |
|
|
|
|
[[one]] [[two]] [tag[three]] -[[four]] +[sort[title]]
|
|
[tag[important]] -[[one][two]] -[[three]] +[sort[-modified]limit[20]]
|
|
|
|
A filter string consists of one or more filter operations, each comprising one or more filter operators with associated operands.
|
|
|
|
The operators look like `[operator[operand]]`, where `operator` is one of:
|
|
* ''title'': selects the tiddler with the title given in the operand
|
|
* ''is'': tests whether a tiddler is a member of the system defined set named in the operand (see below)
|
|
* ''has'': tests whether a tiddler has a specified field
|
|
* ''tag'': tests whether a given tag is (`[tag[mytag]]`) or is not (`[!tag[mytag]]`) present on the tiddler
|
|
* ''<field>'': tests whether a tiddler field has a specified value (`[modifier[Jeremy]]`) or not (`[!modifier[Jeremy]]`)
|
|
|
|
An operator can be negated with by preceding it with `!`, for example `[!tag[Tommy]]` selects the tiddlers that are not tagged with `Tommy`.
|
|
|
|
The operator defaults to `title` if omitted, so `[[HelloThere]]` is equivalent to `[title[HelloThere]]`. If there are no spaces in the title, then the double square brackets can also be omitted: `HelloThere`.
|
|
|
|
The operands available with the `is` operator are:
|
|
* ''tiddler'': selects all ordinary (non-shadow) tiddlers
|
|
|
|
Operators are combined into logically ANDed expressions by bashing them together and merging the square brackets:
|
|
{{{
|
|
[tag[one]] [tag[two]] ---> [tag[one]tag[two]]
|
|
}}}
|
|
|
|
Operations can be preceded with `-` to negate their action, removing the selected tiddlers from the results. For example, `[tag[Tommy]] -HelloThere -[[Another One]]` selects all tiddlers tagged with `Tommy` except those titled `HelloThere` or `Another One`.
|
|
|
|
Operations can be preceded with `+` in order to make them apply to all of the current results, rather than the original source. For example, `[tag[Jeremy]] [tag[Tommy]] +[sort[title]]` selects the tiddlers tagged `Tommy` or `Jeremy`, and sorts them by the `title` field.
|
|
|
|
Filters are processed with the following elements:
|
|
* a string of filter operations, each made up of one or more filter operators
|
|
* the incoming source tiddlers
|
|
* the overall result stack
|
|
* the subresult stack of the tiddlers selected by the current operation
|
|
|
|
\*/
|
|
(function(){
|
|
|
|
/*jslint node: true, browser: true */
|
|
/*global $tw: false */
|
|
"use strict";
|
|
|
|
exports.filterTiddlers = function(filterString) {
|
|
var fn = this.compileFilter(filterString);
|
|
return fn.call(this,this.tiddlers);
|
|
};
|
|
|
|
/*
|
|
Compiling a filter gives a JavaScript function that is invoked as `this.filter(source)`, where `source` is a hashmap of source tiddler titles (the values don't matter, so it is possible to use a store or a changes object). It returns an array of tiddler titles that satisfy the filter
|
|
*/
|
|
exports.compileFilter = function(filterString) {
|
|
var filter = this.parseFilter(filterString),
|
|
output = [],
|
|
t,operation,operationInfo,type,p,operator,operatorInfo,fn;
|
|
output.push(this.filterFragments.prologue);
|
|
for(t=0; t<filter.length; t++) {
|
|
operation = filter[t];
|
|
operationInfo = this.filterFragments.operation.prefix[operation.prefix || ""];
|
|
output.push(operationInfo.prologue);
|
|
type = "selector";
|
|
if(operation.prefix === "+") {
|
|
type = "filter";
|
|
}
|
|
for(p=0; p<operation.operators.length; p++) {
|
|
operator = operation.operators[p];
|
|
operatorInfo = this.operators[operator.operator];
|
|
if(!operatorInfo) { // Check for it being a field operator
|
|
operatorInfo = this.operators["field"];
|
|
}
|
|
output.push(operatorInfo[type](operator));
|
|
type = "filter";
|
|
}
|
|
output.push(operationInfo.epilogue);
|
|
}
|
|
output.push(this.filterFragments.epilogue);
|
|
try {
|
|
/*jslint evil: true */
|
|
fn = eval(output.join("\n"));
|
|
} catch(ex) {
|
|
throw "Error in filter expression: " + ex;
|
|
}
|
|
return fn;
|
|
};
|
|
|
|
exports.filterFragments = {
|
|
prologue: "(function(source) {\nvar results = [], subResults;",
|
|
epilogue: "return results;\n})",
|
|
operation: {
|
|
prefix: {
|
|
"": {
|
|
prologue: "subResults = [];",
|
|
epilogue: "$tw.utils.pushTop(results,subResults);"
|
|
},
|
|
"+": {
|
|
prologue: "subResults = results.slice(0);\nresults.splice(0,results.length);",
|
|
epilogue: "$tw.utils.pushTop(results,subResults);"
|
|
},
|
|
"-": {
|
|
prologue: "subResults = [];",
|
|
epilogue: "$tw.utils.removeArrayEntries(results,subResults);"
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
exports.operators = {
|
|
"title": {
|
|
selector: function(operator) {
|
|
return "if($tw.utils.hop(source,\"" + $tw.utils.stringify(operator.operand) + "\")) {$tw.utils.pushTop(subResults,\"" + $tw.utils.stringify(operator.operand) + "\");}";
|
|
},
|
|
filter: function(operator) {
|
|
return "if(subResults.indexOf(\"" + $tw.utils.stringify(operator.operand) + "\") !== -1) {subResults = [\"" + $tw.utils.stringify(operator.operand) + "\"];} else {subResults = [];}";
|
|
}
|
|
},
|
|
"is": {
|
|
selector: function(operator) {
|
|
switch(operator.operand) {
|
|
case "tiddler":
|
|
if(operator.prefix === "!") {
|
|
return "subResults = [];";
|
|
} else {
|
|
return "for(var title in source) {$tw.utils.pushTop(subResults,title);}";
|
|
}
|
|
break;
|
|
default:
|
|
throw "Unknown operand for 'is' filter operator";
|
|
}
|
|
},
|
|
filter: function(operator) {
|
|
switch(operator.operand) {
|
|
case "tiddler":
|
|
if(operator.prefix === "!") {
|
|
return "subResults = [];";
|
|
} else {
|
|
return "";
|
|
}
|
|
break;
|
|
default:
|
|
throw "Unknown operand for 'is' filter operator";
|
|
}
|
|
}
|
|
},
|
|
"tag": {
|
|
selector: function(operator) {
|
|
var op = operator.prefix === "!" ? "!" : "";
|
|
return "for(var title in source) {if(" + op + "this.getTiddler(title).hasTag(\"" + $tw.utils.stringify(operator.operand) + "\")) {$tw.utils.pushTop(subResults,title);}}";
|
|
},
|
|
filter: function(operator) {
|
|
var op = operator.prefix === "!" ? "" : "!";
|
|
return "for(var r=subResults.length-1; r>=0; r--) {if(" + op + "this.getTiddler(subResults[r]).hasTag(\"" + $tw.utils.stringify(operator.operand) + "\")) {subResults.splice(r,1);}}";
|
|
}
|
|
},
|
|
"has": {
|
|
selector: function(operator) {
|
|
var op = operator.prefix === "!" ? "=" : "!";
|
|
return "for(var title in source) {if(this.getTiddler(title).fields[\"" + $tw.utils.stringify(operator.operand) + "\"] " + op + "== undefined) {$tw.utils.pushTop(subResults,title);}}";
|
|
},
|
|
filter: function(operator) {
|
|
var op = operator.prefix === "!" ? "!" : "=";
|
|
return "for(var r=subResults.length-1; r>=0; r--) {if(this.getTiddler(subResults[r]).fields[\"" + $tw.utils.stringify(operator.operand) + "\"] " + op + "== undefined) {subResults.splice(r,1);}}";
|
|
}
|
|
},
|
|
"sort": {
|
|
selector: function(operator) {
|
|
throw "Cannot use sort operator at the start of a filter operation";
|
|
},
|
|
filter: function(operator) {
|
|
var desc = operator.prefix === "!" ? "true" : "false";
|
|
return "this.sortTiddlers(subResults,\"" + $tw.utils.stringify(operator.operand) + "\"," + desc + ");";
|
|
}
|
|
},
|
|
"field": {
|
|
selector: function(operator) {
|
|
var op = operator.prefix === "!" ? "!" : "=";
|
|
return "for(var title in source) {if(this.getTiddler(title).fields[\"" + $tw.utils.stringify(operator.operator) + "\"] " + op + "== \"" + operator.operand + "\") {$tw.utils.pushTop(subResults,title);}}";
|
|
},
|
|
filter: function(operator) {
|
|
var op = operator.prefix === "!" ? "=" : "!";
|
|
return "for(var r=subResults.length-1; r>=0; r--) {if(this.getTiddler(subResults[r]).fields[\"" + $tw.utils.stringify(operator.operator) + "\"] " + op + "== \"" + operator.operand + "\") {subResults.splice(r,1);}}";
|
|
}
|
|
}
|
|
};
|
|
|
|
/*
|
|
Parses an operation within a filter string
|
|
results: Array of array of operator nodes into which results should be inserted
|
|
filterString: filter string
|
|
p: start position within the string
|
|
Returns the new start position, after the parsed operation
|
|
*/
|
|
function parseFilterOperation(operators,filterString,p) {
|
|
var operator, operand, bracketPos;
|
|
// Skip the starting square bracket
|
|
if(filterString[p++] !== "[") {
|
|
throw "Missing [ in filter expression";
|
|
}
|
|
// Process each operator in turn
|
|
do {
|
|
operator = {};
|
|
// Check for an operator prefix
|
|
if(filterString[p] === "!") {
|
|
operator.prefix = filterString[p++];
|
|
}
|
|
// Get the operator name
|
|
bracketPos = filterString.indexOf("[",p);
|
|
if(bracketPos === -1) {
|
|
throw "Missing [ in filter expression";
|
|
}
|
|
operator.operator = filterString.substring(p,bracketPos);
|
|
if(operator.operator === "") {
|
|
operator.operator = "title";
|
|
}
|
|
p = bracketPos + 1;
|
|
// Get the operand
|
|
bracketPos = filterString.indexOf("]",p);
|
|
if(bracketPos === -1) {
|
|
throw "Missing ] in filter expression";
|
|
}
|
|
operator.operand = filterString.substring(p,bracketPos);
|
|
p = bracketPos + 1;
|
|
// Push this operator
|
|
operators.push(operator);
|
|
} while(filterString[p] !== "]");
|
|
// Skip the ending square bracket
|
|
if(filterString[p++] !== "]") {
|
|
throw "Missing ] in filter expression";
|
|
}
|
|
// Return the parsing position
|
|
return p;
|
|
}
|
|
|
|
/*
|
|
Parse a filter string
|
|
*/
|
|
exports.parseFilter = function(filterString) {
|
|
filterString = filterString || "";
|
|
var results = [], // Array of arrays of operator nodes {operator:,operand:}
|
|
p = 0, // Current position in the filter string
|
|
match;
|
|
var whitespaceRegExp = /(\s+)/mg,
|
|
operandRegExp = /((?:\+|\-)?)(?:(\[)|("(?:[^"])*")|('(?:[^'])*')|([^\s\[\]]+))/mg;
|
|
while(p < filterString.length) {
|
|
// Skip any whitespace
|
|
whitespaceRegExp.lastIndex = p;
|
|
match = whitespaceRegExp.exec(filterString);
|
|
if(match && match.index === p) {
|
|
p = p + match[0].length;
|
|
}
|
|
// Match the start of the operation
|
|
if(p < filterString.length) {
|
|
operandRegExp.lastIndex = p;
|
|
match = operandRegExp.exec(filterString);
|
|
if(!match || match.index !== p) {
|
|
throw "Syntax error in filter expression";
|
|
}
|
|
var operation = {
|
|
prefix: "",
|
|
operators: []
|
|
};
|
|
if(match[1]) {
|
|
operation.prefix = match[1];
|
|
p++;
|
|
}
|
|
if(match[2]) { // Opening square bracket
|
|
p = parseFilterOperation(operation.operators,filterString,p);
|
|
} else {
|
|
p = match.index + match[0].length;
|
|
}
|
|
if(match[3] || match[4] || match[5]) { // Double quoted string, single quoted string or unquoted title
|
|
operation.operators.push(
|
|
{operator: "title", operand: match[3] || match[4] || match[5]}
|
|
);
|
|
}
|
|
results.push(operation);
|
|
}
|
|
}
|
|
return results;
|
|
};
|
|
|
|
})();
|