changeset 1833:21c792334c2e sensible-delimited-data-strings

Rewrite all the DelimitedDataString stuff so as to return vectors of individual cell strings rather than having the classes add the delimiters themselves. Rename accordingly to names based on StringExport. Take advantage of this in the CSV writer code so as to properly quote cells that contain delimiter characters.
author Chris Cannam
date Fri, 03 Apr 2020 17:11:05 +0100
parents 7c92c644db20
children 735b0ccd3f4a
files base/Event.h base/EventSeries.cpp base/EventSeries.h base/StringBits.cpp base/StringBits.h data/fileio/CSVFileWriter.cpp data/fileio/CSVStreamWriter.h data/fileio/test/CSVStreamWriterTest.h data/model/AlignmentModel.h data/model/BasicCompressedDenseThreeDimensionalModel.cpp data/model/BasicCompressedDenseThreeDimensionalModel.h data/model/BoxModel.h data/model/Dense3DModelPeakCache.h data/model/DenseTimeValueModel.cpp data/model/DenseTimeValueModel.h data/model/EditableDenseThreeDimensionalModel.cpp data/model/EditableDenseThreeDimensionalModel.h data/model/FFTModel.h data/model/ImageModel.h data/model/Model.h data/model/NoteModel.h data/model/RegionModel.h data/model/SparseOneDimensionalModel.h data/model/SparseTimeValueModel.h data/model/TextModel.h
diffstat 25 files changed, 301 insertions(+), 269 deletions(-) [+]
line wrap: on
line diff
--- a/base/Event.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/base/Event.h	Fri Apr 03 17:11:05 2020 +0100
@@ -366,9 +366,9 @@
         return n;
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions opts,
-                                       ExportNameOptions nameOpts) const {
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions opts,
+                           ExportNameOptions nameOpts) const {
 
         QStringList list;
 
@@ -400,13 +400,18 @@
         }
         
         list << "label";
+
+        QVector<QString> sv;
+        for (QString s: list) {
+            sv.push_back(s.toUpper());
+        }
+        return sv;
+    }
+
+    QVector<QString>
+    toStringExportRow(DataExportOptions opts,
+                      sv_samplerate_t sampleRate) const {
         
-        return list.join(delimiter).toUpper();
-    }
-    
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions opts,
-                                  sv_samplerate_t sampleRate) const {
         QStringList list;
 
         if (opts & DataExportWriteTimeInFrames) {
@@ -441,8 +446,8 @@
         // facility for the user to customise it
         if (m_uri != "") list << m_uri;
         if (m_label != "") list << m_label;
-        
-        return list.join(delimiter);
+
+        return list.toVector();
     }
     
     uint hash(uint seed = 0) const {
--- a/base/EventSeries.cpp	Fri Apr 03 12:12:02 2020 +0100
+++ b/base/EventSeries.cpp	Fri Apr 03 17:11:05 2020 +0100
@@ -16,6 +16,9 @@
 
 #include <QMutexLocker>
 
+using std::vector;
+using std::string;
+
 EventSeries::EventSeries(const EventSeries &other) :
     EventSeries(other, QMutexLocker(&other.m_mutex))
 {
@@ -597,32 +600,28 @@
     out << indent << "</dataset>\n";
 }
 
-QString
-EventSeries::getDelimitedDataHeaderLine(QString delimiter,
-                                        DataExportOptions opts,
-                                        Event::ExportNameOptions nopts) const
+QVector<QString>
+EventSeries::getStringExportHeaders(DataExportOptions opts,
+                                    Event::ExportNameOptions nopts) const
 {
     if (m_events.empty()) {
-        return QString();
+        return {};
     } else {
-        return m_events.begin()->getDelimitedDataHeaderLine(delimiter,
-                                                            opts,
-                                                            nopts);
+        return m_events.begin()->getStringExportHeaders(opts, nopts);
     }
 }
 
-QString
-EventSeries::toDelimitedDataString(QString delimiter,
-                                   DataExportOptions options,
-                                   sv_frame_t startFrame,
-                                   sv_frame_t duration,
-                                   sv_samplerate_t sampleRate,
-                                   sv_frame_t resolution,
-                                   Event fillEvent) const
+QVector<QVector<QString>>
+EventSeries::toStringExportRows(DataExportOptions options,
+                                sv_frame_t startFrame,
+                                sv_frame_t duration,
+                                sv_samplerate_t sampleRate,
+                                sv_frame_t resolution,
+                                Event fillEvent) const
 {
     QMutexLocker locker(&m_mutex);
 
-    QString s;
+    QVector<QVector<QString>> rows;
 
     const sv_frame_t end = startFrame + duration;
 
@@ -632,10 +631,7 @@
     if (!(options & DataExportFillGaps)) {
         
         while (pitr != m_events.end() && pitr->getFrame() < end) {
-            s += pitr->toDelimitedDataString(delimiter,
-                                             options,
-                                             sampleRate);
-            s += "\n";
+            rows.push_back(pitr->toStringExportRow(options, sampleRate));
             ++pitr;
         }
 
@@ -659,22 +655,19 @@
         // distance) or a default fill point
         while (f < end) {
             if (pitr != m_events.end() && pitr->getFrame() <= f) {
-                s += pitr->toDelimitedDataString
-                    (delimiter,
-                     options & ~DataExportFillGaps,
-                     sampleRate);
+                rows.push_back(pitr->toStringExportRow
+                               (options & ~DataExportFillGaps,
+                                sampleRate));
                 ++pitr;
             } else {
-                s += fillEvent.withFrame(f).toDelimitedDataString
-                    (delimiter,
-                     options & ~DataExportFillGaps,
-                     sampleRate);
+                rows.push_back(fillEvent.withFrame(f).toStringExportRow
+                               (options & ~DataExportFillGaps,
+                                sampleRate));
             }
-            s += "\n";
             f += resolution;
         }
     }
     
-    return s;
+    return rows;
 }
 
--- a/base/EventSeries.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/base/EventSeries.h	Fri Apr 03 17:11:05 2020 +0100
@@ -19,6 +19,8 @@
 #include "XmlExportable.h"
 
 #include <set>
+#include <string>
+#include <vector>
 #include <functional>
 
 #include <QMutex>
@@ -221,24 +223,24 @@
                Event::ExportNameOptions) const;
 
     /**
-     * Emit a label for each column that would be written by
-     * toDelimitedDataString, separated by the given delimiter.
+     * Return a label for each column that would be written by
+     * toStringExportRows.
      */
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options,
-                                       Event::ExportNameOptions) const;
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options,
+                           Event::ExportNameOptions) const;
     
     /**
-     * Emit events starting within the given range to a delimited
-     * (e.g. comma-separated) data format.
+     * Emit events starting within the given range as string rows
+     * ready for conversion to an e.g. comma-separated data format.
      */
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration,
-                                  sv_samplerate_t sampleRate,
-                                  sv_frame_t resolution,
-                                  Event fillEvent) const;
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration,
+                       sv_samplerate_t sampleRate,
+                       sv_frame_t resolution,
+                       Event fillEvent) const;
     
 private:
     mutable QMutex m_mutex;
--- a/base/StringBits.cpp	Fri Apr 03 12:12:02 2020 +0100
+++ b/base/StringBits.cpp	Fri Apr 03 17:11:05 2020 +0100
@@ -151,3 +151,20 @@
     }
 }
 
+QString
+StringBits::joinDelimited(QVector<QString> row, QString delimiter)
+{
+    QString s;
+    for (auto col: row) {
+        if (s != "") {
+            s += delimiter;
+        }
+        if (col.contains(delimiter)) {
+            col.replace("\"", "\"\"");
+            col = "\"" + col + "\"";
+        }
+        s += col;
+    }
+    return s;    
+}
+
--- a/base/StringBits.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/base/StringBits.h	Fri Apr 03 17:11:05 2020 +0100
@@ -55,6 +55,16 @@
      * analogous to the behaviour of splitQuoted).
      */
     static QStringList split(QString s, QChar separator, bool quoted);
+
+    /**
+     * Join a vector of strings into a single string, with the
+     * delimiter as the joining string. If a string contains the
+     * delimiter already, quote it with double-quotes, replacing any
+     * existing double-quotes within it by a pair of double-quotes, as
+     * specified in RFC 4180 Common Format and MIME Type for
+     * Comma-Separated Values (CSV) Files.
+     */
+    static QString joinDelimited(QVector<QString> row, QString delimiter);
 };
 
 #endif
--- a/data/fileio/CSVFileWriter.cpp	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/fileio/CSVFileWriter.cpp	Fri Apr 03 17:11:05 2020 +0100
@@ -86,7 +86,9 @@
         QTextStream out(&file);
 
         if (m_options & DataExportIncludeHeader) {
-            out << m_model->getDelimitedDataHeaderLine(m_delimiter, m_options)
+            out << StringBits::joinDelimited
+                (m_model->getStringExportHeaders(m_options),
+                 m_delimiter)
                 << endl;
         }
         
--- a/data/fileio/CSVStreamWriter.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/fileio/CSVStreamWriter.h	Fri Apr 03 17:11:05 2020 +0100
@@ -20,7 +20,9 @@
 #include "base/Selection.h"
 #include "base/ProgressReporter.h"
 #include "base/DataExportOptions.h"
+#include "base/StringBits.h"
 #include "data/model/Model.h"
+
 #include <QString>
 #include <algorithm>
 #include <numeric>
@@ -68,20 +70,21 @@
 
             const auto start = readPtr;
             const auto end = std::min(start + blockSize, endFrame);
-            const auto data = model.toDelimitedDataString(
-                delimiter,
+            const auto data = model.toStringExportRows(
                 options,
                 start,
                 end - start
-            ).trimmed();
+            );
 
-            if ( data != "" ) {
-                if (started) {
-                    oss << "\n";
-                } else {
-                    started = true;
+            if (!data.empty()) {
+                for (const auto &row: data) {
+                    if (started) {
+                        oss << "\n";
+                    } else {
+                        started = true;
+                    }
+                    oss << StringBits::joinDelimited(row, delimiter);
                 }
-                oss << data;
             }
 
             nFramesWritten += end - start;
@@ -120,7 +123,7 @@
     };
     MultiSelection regions;
     regions.addSelection(all);
-    return CSVStreamWriter::writeInChunks(
+    return writeInChunks(
         oss,
         model,
         regions,
@@ -141,7 +144,7 @@
               const sv_frame_t blockSize = 16384)
 {
     const Selection empty;
-    return CSVStreamWriter::writeInChunks(
+    return writeInChunks(
         oss,
         model,
         empty,
--- a/data/fileio/test/CSVStreamWriterTest.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/fileio/test/CSVStreamWriterTest.h	Fri Apr 03 17:11:05 2020 +0100
@@ -94,6 +94,7 @@
 
         std::ostringstream oss;
         const auto result = CSVStreamWriter::writeInChunks(oss, mwm);
+        
         QVERIFY( oss.str() == getExpectedString() );
         QVERIFY( result );
     }
@@ -303,9 +304,12 @@
 //        qDebug("Create Expected Output\n");
 
         // NB. removed end line break
-        const auto expectedOutput =
-            notes.toDelimitedDataString(",", {}, 0, notes.getEndFrame())
-            .trimmed();
+        QString expectedOutput;
+        auto rows = notes.toStringExportRows({}, 0, notes.getEndFrame());
+        for (auto row: rows) {
+            expectedOutput += StringBits::joinDelimited(row, ",") + "\n";
+        }
+        expectedOutput = expectedOutput.trimmed();
 
         StubReporter reporter { []() -> bool { return false; } };
         std::ostringstream oss;
--- a/data/model/AlignmentModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/AlignmentModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -77,13 +77,14 @@
                QString indent = "",
                QString extraAttributes = "") const override;
 
-    QString getDelimitedDataHeaderLine(QString, DataExportOptions) const override {
-        return "";
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions) const override {
+        return {};
     }
-    
-    QString toDelimitedDataString(QString, DataExportOptions,
-                                  sv_frame_t, sv_frame_t) const override {
-        return "";
+
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions, sv_frame_t, sv_frame_t) const override {
+        return {};
     }
 
 signals:
--- a/data/model/BasicCompressedDenseThreeDimensionalModel.cpp	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/BasicCompressedDenseThreeDimensionalModel.cpp	Fri Apr 03 17:11:05 2020 +0100
@@ -498,37 +498,40 @@
     return m_completion;
 }
 
-QString
-BasicCompressedDenseThreeDimensionalModel::getDelimitedDataHeaderLine(QString delimiter,
-                                                                      DataExportOptions) const
+QVector<QString>
+BasicCompressedDenseThreeDimensionalModel::getStringExportHeaders(DataExportOptions)
+    const
 {
-    QStringList list;
+    QVector<QString> sv;
     for (int i = 0; i < m_yBinCount; ++i) {
-        list << QString("Bin%1").arg(i+1);
+        sv.push_back(QString("Bin%1").arg(i+1));
     }
-    return list.join(delimiter);
+    return sv;
 }    
-
-QString
-BasicCompressedDenseThreeDimensionalModel::toDelimitedDataString(QString delimiter,
-                                                          DataExportOptions,
-                                                          sv_frame_t startFrame,
-                                                          sv_frame_t duration) const
+    
+QVector<QVector<QString>>
+BasicCompressedDenseThreeDimensionalModel::toStringExportRows(DataExportOptions,
+                                                              sv_frame_t startFrame,
+                                                              sv_frame_t duration)
+    const
 {
     QReadLocker locker(&m_lock);
-    QString s;
+
+    QVector<QVector<QString>> rows;
+
     for (int i = 0; in_range_for(m_data, i); ++i) {
         Column c = getColumn(i);
         sv_frame_t fr = m_startFrame + i * m_resolution;
         if (fr >= startFrame && fr < startFrame + duration) {
-            QStringList list;
+            QVector<QString> row;
             for (int j = 0; in_range_for(c, j); ++j) {
-                list << QString("%1").arg(c.at(j));
+                row << QString("%1").arg(c.at(j));
             }
-            s += list.join(delimiter) + "\n";
+            rows.push_back(row);
         }
     }
-    return s;
+    
+    return rows;
 }
 
 void
--- a/data/model/BasicCompressedDenseThreeDimensionalModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/BasicCompressedDenseThreeDimensionalModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -181,13 +181,13 @@
 
     QString getTypeName() const override { return tr("Editable Dense 3-D"); }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions opts) const override;
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override;
 
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override;
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override;
 
     void toXml(QTextStream &out,
                        QString indent = "",
--- a/data/model/BoxModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/BoxModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -348,8 +348,9 @@
         m_events.toXml(out, indent, QString("dimensions=\"2\""), options);
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions opts) const override {
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions opts) const override {
+
         QStringList list;
 
         // These are considered API rather than human-readable text -
@@ -363,23 +364,27 @@
 
         list << "extent start" << "extent end" << "label";
 
-        return list.join(delimiter).toUpper();
+        QVector<QString> sv;
+        for (QString s: list) {
+            sv.push_back(s.toUpper());
+        }
+        return sv;
     }
     
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions opts,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override {
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions opts,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override {
 
         // We need a custom format here
 
         EventVector ee = m_events.getEventsSpanning(startFrame, duration);
 
-        QString s;
+        QVector<QVector<QString>> rows;
         
         for (auto e: ee) {
 
-            QStringList list;
+            QVector<QString> list;
 
             if (opts & DataExportWriteTimeInFrames) {
                 
@@ -405,10 +410,10 @@
                 list << e.getLabel();
             }
 
-            s += list.join(delimiter) + "\n";
+            rows.push_back(list);
         }
 
-        return s;
+        return rows;
     }
 
 protected:
--- a/data/model/Dense3DModelPeakCache.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/Dense3DModelPeakCache.h	Fri Apr 03 17:11:05 2020 +0100
@@ -119,13 +119,14 @@
         return source ? source->getCompletion() : 100;
     }
 
-    QString getDelimitedDataHeaderLine(QString, DataExportOptions) const override {
-        return "";
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions) const override {
+        return {};
     }
-    
-    QString toDelimitedDataString(QString, DataExportOptions,
-                                  sv_frame_t, sv_frame_t) const override {
-        return "";
+
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions, sv_frame_t, sv_frame_t) const override {
+        return {};
     }
 
 protected slots:
--- a/data/model/DenseTimeValueModel.cpp	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/DenseTimeValueModel.cpp	Fri Apr 03 17:11:05 2020 +0100
@@ -17,41 +17,42 @@
 
 #include <QStringList>
 
-QString
-DenseTimeValueModel::getDelimitedDataHeaderLine(QString delimiter,
-                                                DataExportOptions) const
+using namespace std;
+
+QVector<QString>
+DenseTimeValueModel::getStringExportHeaders(DataExportOptions) const
 {
     int ch = getChannelCount();
-    QStringList list;
+    QVector<QString> sv;
     for (int i = 0; i < ch; ++i) {
-        list << QString("Channel%1").arg(i+1);
+        sv.push_back(QString("Channel%1").arg(i+1));
     }
-    return list.join(delimiter);
+    return sv;
 }
 
-QString
-DenseTimeValueModel::toDelimitedDataString(QString delimiter,
-                                           DataExportOptions,
-                                           sv_frame_t startFrame,
-                                           sv_frame_t duration) const
+QVector<QVector<QString>>
+DenseTimeValueModel::toStringExportRows(DataExportOptions,
+                                        sv_frame_t startFrame,
+                                        sv_frame_t duration) const
 {
     int ch = getChannelCount();
 
-    if (duration <= 0) return "";
+    if (duration <= 0) return {};
 
     auto data = getMultiChannelData(0, ch - 1, startFrame, duration);
 
-    if (data.empty() || data[0].empty()) return "";
+    if (data.empty() || data[0].empty()) return {};
     
-    QStringList list;
+    QVector<QVector<QString>> rows;
+
     for (sv_frame_t i = 0; in_range_for(data[0], i); ++i) {
-        QStringList parts;
-        parts << QString("%1").arg(startFrame + i);
+        QVector<QString> row;
+        row.push_back(QString("%1").arg(startFrame + i));
         for (int c = 0; in_range_for(data, c); ++c) {
-            parts << QString("%1").arg(data[c][i]);
+            row.push_back(QString("%1").arg(data[c][i]));
         }
-        list << parts.join(delimiter);
+        rows.push_back(row);
     }
 
-    return list.join("\n");
+    return rows;
 }
--- a/data/model/DenseTimeValueModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/DenseTimeValueModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -82,13 +82,13 @@
     bool canPlay() const override { return true; }
     QString getDefaultPlayClipId() const override { return ""; }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options) const override;
-    
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override;
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override;
+
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override;
 
     QString getTypeName() const override { return tr("Dense Time-Value"); }
 };
--- a/data/model/EditableDenseThreeDimensionalModel.cpp	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/EditableDenseThreeDimensionalModel.cpp	Fri Apr 03 17:11:05 2020 +0100
@@ -351,36 +351,38 @@
     return m_completion;
 }
 
-QString
-EditableDenseThreeDimensionalModel::getDelimitedDataHeaderLine(QString delimiter,
-                                                               DataExportOptions) const
+QVector<QString>
+EditableDenseThreeDimensionalModel::getStringExportHeaders(DataExportOptions)
+    const
 {
-    QStringList list;
+    QVector<QString> sv;
     for (int i = 0; i < m_yBinCount; ++i) {
-        list << QString("Bin%1").arg(i+1);
+        sv.push_back(QString("Bin%1").arg(i+1));
     }
-    return list.join(delimiter);
+    return sv;
 }    
     
-QString
-EditableDenseThreeDimensionalModel::toDelimitedDataString(QString delimiter,
-                                                          DataExportOptions,
-                                                          sv_frame_t startFrame,
-                                                          sv_frame_t duration) const
+QVector<QVector<QString>>
+EditableDenseThreeDimensionalModel::toStringExportRows(DataExportOptions,
+                                                       sv_frame_t startFrame,
+                                                       sv_frame_t duration)
+    const
 {
     QMutexLocker locker(&m_mutex);
-    QString s;
+
+    QVector<QVector<QString>> rows;
+
     for (int i = 0; in_range_for(m_data, i); ++i) {
         sv_frame_t fr = m_startFrame + i * m_resolution;
         if (fr >= startFrame && fr < startFrame + duration) {
-            QStringList list;
+            QVector<QString> row;
             for (int j = 0; in_range_for(m_data.at(i), j); ++j) {
-                list << QString("%1").arg(m_data.at(i).at(j));
+                row.push_back(QString("%1").arg(m_data.at(i).at(j)));
             }
-            s += list.join(delimiter) + "\n";
+            rows.push_back(row);
         }
     }
-    return s;
+    return rows;
 }
 
 void
--- a/data/model/EditableDenseThreeDimensionalModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/EditableDenseThreeDimensionalModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -172,13 +172,13 @@
 
     QString getTypeName() const override { return tr("Editable Dense 3-D"); }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions opts) const override;
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override;
 
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override;
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override;
 
     void toXml(QTextStream &out,
                        QString indent = "",
--- a/data/model/FFTModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/FFTModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -99,12 +99,14 @@
     float getBinValue(int n) const override;
     QString getBinName(int n) const override;
 
-    QString getDelimitedDataHeaderLine(QString, DataExportOptions) const override {
-        return "";
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions) const override {
+        return {};
     }
-    QString toDelimitedDataString(QString, DataExportOptions,
-                                  sv_frame_t, sv_frame_t) const override {
-        return "";
+
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions, sv_frame_t, sv_frame_t) const override {
+        return {};
     }
 
     // FFTModel methods:
--- a/data/model/ImageModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/ImageModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -275,27 +275,23 @@
         m_events.toXml(out, indent, QString("dimensions=\"1\""), options);
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options) const override {
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override {
         Event::ExportNameOptions nameOpts;
         nameOpts.uriAttributeName = "image";
-
-        return m_events.getDelimitedDataHeaderLine(delimiter,
-                                                   options,
-                                                   nameOpts);
+        return m_events.getStringExportHeaders(options, nameOpts);
     }
     
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override {
-        return m_events.toDelimitedDataString(delimiter,
-                                              options,
-                                              startFrame,
-                                              duration,
-                                              m_sampleRate,
-                                              m_resolution,
-                                              Event().withValue(0.f));
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override {
+        return m_events.toStringExportRows(options,
+                                           startFrame,
+                                           duration,
+                                           m_sampleRate,
+                                           m_resolution,
+                                           Event().withValue(0.f));
     }
     
 protected:
--- a/data/model/Model.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/Model.h	Fri Apr 03 17:11:05 2020 +0100
@@ -275,20 +275,20 @@
                QString extraAttributes = "") const override;
 
     /**
-     * Emit a label for each column that would be written by
-     * toDelimitedDataString, separated by the given delimiter.
+     * Return a label for each column that would be written by
+     * toStringExportRows.
      */
-    virtual QString getDelimitedDataHeaderLine(QString delimiter,
-                                               DataExportOptions options) const = 0;
+    virtual QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const = 0;
     
     /**
-     * Emit the contents of the model within the given range to a
-     * delimited (e.g. comma-separated) data format.
+     * Emit events starting within the given range as string rows
+     * ready for conversion to an e.g. comma-separated data format.
      */
-    virtual QString toDelimitedDataString(QString delimiter,
-                                          DataExportOptions options,
-                                          sv_frame_t startFrame,
-                                          sv_frame_t duration) const = 0;
+    virtual QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const = 0;
 
 signals:
     /**
--- a/data/model/NoteModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/NoteModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -408,20 +408,17 @@
         m_events.toXml(out, indent, QString("dimensions=\"3\""));
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options) const override {
-        return m_events.getDelimitedDataHeaderLine(delimiter,
-                                                   options,
-                                                   Event::ExportNameOptions());
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override {
+        return m_events.getStringExportHeaders(options, {});
     }
     
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override {
-        return m_events.toDelimitedDataString
-            (delimiter,
-             options,
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override {
+        return m_events.toStringExportRows
+            (options,
              startFrame,
              duration,
              m_sampleRate,
--- a/data/model/RegionModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/RegionModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -340,20 +340,17 @@
         m_events.toXml(out, indent, QString("dimensions=\"3\""));
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options) const override {
-        return m_events.getDelimitedDataHeaderLine(delimiter,
-                                                   options,
-                                                   Event::ExportNameOptions());
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override {
+        return m_events.getStringExportHeaders(options, {});
     }
     
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override {
-        return m_events.toDelimitedDataString
-            (delimiter,
-             options,
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override {
+        return m_events.toStringExportRows
+            (options,
              startFrame,
              duration,
              m_sampleRate,
--- a/data/model/SparseOneDimensionalModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/SparseOneDimensionalModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -308,24 +308,21 @@
         m_events.toXml(out, indent, QString("dimensions=\"1\""));
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options) const override {
-        return m_events.getDelimitedDataHeaderLine(delimiter,
-                                                   options,
-                                                   Event::ExportNameOptions());
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override {
+        return m_events.getStringExportHeaders(options, {});
     }
     
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override {
-        return m_events.toDelimitedDataString(delimiter,
-                                              options,
-                                              startFrame,
-                                              duration,
-                                              m_sampleRate,
-                                              m_resolution,
-                                              Event());
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override {
+        return m_events.toStringExportRows(options,
+                                           startFrame,
+                                           duration,
+                                           m_sampleRate,
+                                           m_resolution,
+                                           {});
     }
     
 protected:
--- a/data/model/SparseTimeValueModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/SparseTimeValueModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -347,24 +347,21 @@
         m_events.toXml(out, indent, QString("dimensions=\"2\""));
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options) const override {
-        return m_events.getDelimitedDataHeaderLine(delimiter,
-                                                   options,
-                                                   Event::ExportNameOptions());
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override {
+        return m_events.getStringExportHeaders(options, {});
     }
     
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override {
-        return m_events.toDelimitedDataString(delimiter,
-                                              options,
-                                              startFrame,
-                                              duration,
-                                              m_sampleRate,
-                                              m_resolution,
-                                              Event().withValue(0.f));
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override {
+        return m_events.toStringExportRows(options,
+                                           startFrame,
+                                           duration,
+                                           m_sampleRate,
+                                           m_resolution,
+                                           Event().withValue(0.f));
     }
   
 protected:
--- a/data/model/TextModel.h	Fri Apr 03 12:12:02 2020 +0100
+++ b/data/model/TextModel.h	Fri Apr 03 17:11:05 2020 +0100
@@ -278,26 +278,23 @@
         m_events.toXml(out, indent, QString("dimensions=\"2\""), options);
     }
 
-    QString getDelimitedDataHeaderLine(QString delimiter,
-                                       DataExportOptions options) const override {
+    QVector<QString>
+    getStringExportHeaders(DataExportOptions options) const override {
         Event::ExportNameOptions nameOpts;
         nameOpts.valueAttributeName = "height";
-        return m_events.getDelimitedDataHeaderLine(delimiter,
-                                                   options,
-                                                   nameOpts);
+        return m_events.getStringExportHeaders(options, nameOpts);
     }
     
-    QString toDelimitedDataString(QString delimiter,
-                                  DataExportOptions options,
-                                  sv_frame_t startFrame,
-                                  sv_frame_t duration) const override {
-        return m_events.toDelimitedDataString(delimiter,
-                                              options,
-                                              startFrame,
-                                              duration,
-                                              m_sampleRate,
-                                              m_resolution,
-                                              Event().withValue(0.f));
+    QVector<QVector<QString>>
+    toStringExportRows(DataExportOptions options,
+                       sv_frame_t startFrame,
+                       sv_frame_t duration) const override {
+        return m_events.toStringExportRows(options,
+                                           startFrame,
+                                           duration,
+                                           m_sampleRate,
+                                           m_resolution,
+                                           Event().withValue(0.f));
     }
   
 protected: