From f180eac23a19dc1fa573924a823b3ae5a3a25844 Mon Sep 17 00:00:00 2001
From: Volker Berlin <volker.berlin@googlemail.com>
Date: Sun, 3 Feb 2019 18:00:14 +0100
Subject: [PATCH] add function range #47

---
 src/com/inet/lib/less/FunctionExpression.java | 42 ++++++++++++++++++-
 .../less/samples/less_org_doc/list/range.css  | 16 +++++++
 .../less/samples/less_org_doc/list/range.less | 20 +++++++++
 3 files changed, 77 insertions(+), 1 deletion(-)
 create mode 100644 test/com/inet/lib/less/samples/less_org_doc/list/range.css
 create mode 100644 test/com/inet/lib/less/samples/less_org_doc/list/range.less

diff --git a/src/com/inet/lib/less/FunctionExpression.java b/src/com/inet/lib/less/FunctionExpression.java
index abeacf4a..0304948a 100644
--- a/src/com/inet/lib/less/FunctionExpression.java
+++ b/src/com/inet/lib/less/FunctionExpression.java
@@ -294,6 +294,9 @@ public void appendTo( CssFormatter formatter ) {
                         return;
                     }
                     break;
+                case "range":
+                    range( formatter ).appendTo( formatter );
+                    return;
             }
             if( type == UNKNOWN ) {
                 eval( formatter );
@@ -451,6 +454,9 @@ private void eval( CssFormatter formatter ) {
                 case "extract":
                     extract( formatter );
                     return;
+                case "range":
+                    type = LIST;
+                    return;
                 case "alpha":
                     type = NUMBER;
                     switch( get( 0 ).getDataType( formatter ) ) {
@@ -1028,9 +1034,11 @@ private double getDouble( int idx, double defaultValue, CssFormatter formatter )
      */
     @Override
     public Operation listValue( CssFormatter formatter ) {
-        switch( super.toString().toLowerCase() ) {
+        switch( super.toString() ) {
             case "extract":
                 return extract( formatter ).listValue( formatter );
+            case "range":
+                return range( formatter );
         }
         return super.listValue( formatter );
     }
@@ -1084,4 +1092,36 @@ private Expression extract( CssFormatter formatter ) {
         return ex;
 
     }
+
+    /**
+     * Function range. Generate a list spanning a range of values
+     * 
+     * @param formatter
+     *            current CSS output
+     * @return The operation representing a list of values
+     */
+    private Operation range( CssFormatter formatter ) {
+        type = LIST;
+        double start = get( 0 ).doubleValue( formatter );
+        double end;
+        if( parameters.size() >= 2 ) {
+            end = get( 1 ).doubleValue( formatter );
+        } else {
+            end = start;
+            start = 1;
+        }
+        double step;
+        if( parameters.size() >= 3 ) {
+            step = get( 2 ).doubleValue( formatter );
+        } else {
+            step = 1;
+        }
+        String unit = get( 0 ).unit( formatter );
+        Operation op = new Operation( this, ' ' );
+        while( start <= end ) {
+            op.addOperand( new ValueExpression( this, start + unit ) );
+            start += step;
+        }
+        return op;
+    }
 }
diff --git a/test/com/inet/lib/less/samples/less_org_doc/list/range.css b/test/com/inet/lib/less/samples/less_org_doc/list/range.css
new file mode 100644
index 00000000..9a7a14c0
--- /dev/null
+++ b/test/com/inet/lib/less/samples/less_org_doc/list/range.css
@@ -0,0 +1,16 @@
+simple {
+  value: 1 2 3 4;
+  length: 4;
+}
+full {
+  value: 10px 20px 30px;
+  length: 3;
+}
+empty {
+  value: ;
+  length: 0;
+}
+floating {
+  value: 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2;
+  length: 10;
+}
diff --git a/test/com/inet/lib/less/samples/less_org_doc/list/range.less b/test/com/inet/lib/less/samples/less_org_doc/list/range.less
new file mode 100644
index 00000000..35b4e2e3
--- /dev/null
+++ b/test/com/inet/lib/less/samples/less_org_doc/list/range.less
@@ -0,0 +1,20 @@
+simple {
+    @list: range(4);
+    value: @list;
+    length: length( @list );
+}
+full {
+    @list: range(10px, 30px, 10);
+    value: @list;
+    length: length( @list );
+}
+empty {
+    @list: range(10, 5);
+    value: @list;
+    length: length( @list );
+}
+floating {
+    @list: range(1.4, 3.4, 0.2);
+    value: @list;
+    length: length( @list );
+}
\ No newline at end of file