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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <div id="messages"></div>
            
          
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              body {
    font-family: sans-serif;
}

.Messages {
    max-width: 56em;
    list-style: none;
    padding-left: 0;
}
.Message {
    background: #eef;
    border: solid 2px #cce;
    padding: 1em;
    margin-bottom: 1em;
}
.Message-link {
    color: #339;
    font-weight: bold;
    text-decoration: none;
}

.Error {
    background: #fee;
    padding: 1em;
    color: #633;
    border: solid 2px #c33;
    max-width: 56em;
}

time {
    display: block;
    margin-top: .5em;
    color: #669;
    font-size: .8em;
}
            
          
!
            
              /**
 * Left
 */
class Left {
    constructor(val) {
        this._value = val;
    }

    map() {
        // Left is the sad path
        // so we do nothing
        return this;
    }

    join() {
        // On the sad path, we don't
        // do anything with join
        return this;
    }

    chain() {
        // Boring sad path,
        // do nothing.
        return this;
    }
    
    
    ap() {
        return this;
    }

    toString() {
        const str = this._value.toString();
        return `Left(${$str})`;
    }
    
    static of(val) {
        return new Left(val);
    }
}

/**
 * Right
 */
class Right {
    constructor(val) {
        this._value = val;
    }

    map(fn) {
        return new Right(
            fn(this._value)
        );
    }

    join() {
        if ((this._value instanceof Left)
            || (this._value instanceof Right)) {
            return this._value;
        }
        return this;
    }

    chain(fn) {
        return fn(this._value);
    }
       
    ap(otherEither) {
        const functionToRun = otherEither._value;
        return this.map(functionToRun);
    }

    toString() {
        const str = this._value.toString();
        return `Right(${str})`;
    }
    
    static of(val) {
        return new Right(val);
    }
}

/**
 * Create a new Left
 */
function left(x) {
    return Left.of(x);
}

/**
 * Create a new Right
 */
function right(x) {
    return Right.of(x);
}

/**
 * Either.
 *
 * Run either leftFunc or rightFunc depending on whether or not
 * e is an instance of Left or Right.
 */
function either(leftFunc, rightFunc, e) {
        return (e instanceof Left) ? leftFunc(e._value) : rightFunc(e._value);
}


/**
 * LiftA2
 *
 * Take a function that works with regular values,
 * and make it work with any object that provides
 * .ap()
 */
function liftA2(func) {
    return function runApplicativeFunc(a, b) {
        return b.ap(a.map(func));
    };
}

// CSV Parsing Code
// ---------------------------------------------------------------------------------

/**
 * Split a row string into an array of fields.
 *
 * Note: Don't do this. Use a CSV parsing library
 * like Neat CSV instead.
 * https://github.com/sindresorhus/neat-csv
 */
function splitFields(row) {
    return row.replace(/"(.*)"/, '$1').split('","');
}

/**
 * Zip Row data with header fields to create an object.
 */
function zipRow(headerFields) {
    return function zipRowWithHeaderFields(fieldData) {
        const lengthMatch = (headerFields.length == fieldData.length);
        return (!lengthMatch)
            ? left(new Error("Row has an unexpected number of fields"))
            : right(_.zipObject(headerFields, fieldData));
    };
}

/**
 * Add a human-readable date string to a message object.
 */
function addDateStr(messageObj) {
    const errMsg = 'Unable to parse date stamp in message object';
    const months = [
        'January', 'February', 'March', 'April', 'May', 'June', 'July',
        'August', 'September', 'October', 'November', 'December'
    ];
    const d = new Date(messageObj.datestamp);
    if (isNaN(d)) { return left(new Error(errMsg));  }

    const datestr = `${d.getDate()} ${months[d.getMonth()]} ${d.getFullYear()}`;
    return right({datestr, ...messageObj});
}


const rowToMessage = _.template(`<li class="Message Message--<%= viewed %>">
  <a href="<%= href %>" class="Message-link"><%= content %></a>
  <time datetime="<%= datestamp %>"><%= datestr %></time>
<li>`);

const showError = _.template(`<li class="Error"><%= message %></li>`);

/**
 * Process a row of CSV data an return a list item
 * HTML string.
 */
function processRow(headerFields, row) {
    const rowObjWithDate = right(row)
        .map(splitFields)
        .chain(zipRow(headerFields))
        .chain(addDateStr);
    return either(showError, rowToMessage, rowObjWithDate);
}


/**
 * Split a CSV string into rows.
 *
 * Note: Don't do this. Use a CSV parsing library
 * like Neat CSV instead.
 * https://github.com/sindresorhus/neat-csv
 */
function splitCSVToRows(csvData) {
    // There should always be a header row... so if there's no
    // newline character, something is wrong.
    return (csvData.indexOf('\n') < 0)
        ? left(new Error('No header row found in CSV data'))
        : right(csvData.split('\n'));
}

/**
 * Process rows.
 */
function processRows(headerFields) {
    return function processRowsWithHeaderFields(dataRows) {
        // Note this is Array map, not Either map.
        return dataRows.map(row => processRow(headerFields, row));
    }
}

/**
 * Take an array of messages HTML list items and create an
 * unordered list string.
 */
function showMessages(messages) {
    return `<ul class="Messages">${messages.join('\n')}</ul>`;
}

/**
 * Our main function. Take CSV data and convert it to an
 * HTML string of formatted list items.
 */
function csvToMessages(csvData) {
    const csvRows      = splitCSVToRows(csvData);
    const headerFields = csvRows.map(_.head).map(splitFields);
    const dataRows     = csvRows.map(_.tail);
    const processRowsA = liftA2(processRows);
    const messagesArr  = processRowsA(headerFields, dataRows);
    return either(showError, showMessages, messagesArr);
}

// Data and Main code.
// ---------------------------------------------------------------------------------

const csvData = `"datestamp","content","viewed","href"
"2018-10-27T05:33:34+00:00","@madhatter invited you to tea","unread","https://example.com/invite/tea/3801"
"2018-10-26T13:47:12+00:00","@queenofhearts mentioned you in 'Croquet Tournament' discussion","viewed","https://example.com/discussions/croquet/1168"
"2018-10-25T03:50:08+00:00","@cheshirecat sent you a grin","unread","https://example.com/interactions/grin/88"`;



document.querySelector('#messages').innerHTML = csvToMessages(csvData);
            
          
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