github.com/slspeek/camlistore_namedsearch@v0.0.0-20140519202248-ed6f70f7721a/doc/search-ui.txt (about)

     1  The User Interface's "Search" box accepts predicates of the form "[-]operator:value[:value]".
     2  These predicates may be separated by 'and' or 'or' keywords, or spaces which mean the same
     3  as 'and'. Expressions like this may be grouped with parenthesis. Grouped expressions are 
     4  evaluated first. Grouped expressions may be negated.
     5  An 'and' besides an 'or' is evaluated first. This means for example that
     6  
     7  tag:foo or is:pano tag:bar 
     8  
     9  will return all images having tag foo together with the panorama images having tag bar.
    10  
    11  Negation of a predicate is achieved by prepending a minus sign: -is:landscape will match
    12  with pictures of not landscape ratio.
    13  
    14  For example
    15  
    16      -(after:"2010-01-01" before:"2010-03-02T12:33:44") or loc:"Amsterdam" 
    17  
    18  will return all images having "modtime" outside the specified period, joined with
    19  all images taken in Amsterdam.
    20  
    21  When you need to match a value containing a space, you need to use double quotes around
    22  the value only. For example: tag:"Three word tagname" and not "tag:Three word tagname".
    23  If your value contains double quotes you can use backslash escaping.
    24  For example: attr:bar:"He said: \"Hi\"" 
    25  
    26  Usable operators:
    27      after:         date format is RFC3339, but can be shortened as required.
    28      before:        i.e. 2011-01-01 is Jan 1 of year 2011 and "2011" means the same.
    29      attr:          match on attribute. Use attr:foo:bar to match nodes having their foo
    30                     attribute set to bar.
    31      format:        file's format (or MIME-type) such as jpg, pdf, tiff.
    32      has:location   image has a location (GPSLatitude and GPSLongitude can be
    33                     retrieved from the image's EXIF tags).
    34      loc:           uses the EXIF GPS fields to match images having a location near
    35                     the specified location.  Locations are resolved using
    36                     maps.googleapis.com. For example: loc:"new york, new york" 
    37      is:image       object is an image
    38      is:landscape   the image has a landscape aspect
    39      is:pano        the image's aspect ratio is over 2 - panorama picture.
    40      is:portrait    the image has a portrait aspect.
    41      height:        use height:min-max to match images having a height of at least min 
    42                     and at most max. Use height:min- to specify only an underbound and
    43                     height:-max to specify only an upperbound. 
    44                     Exact matches should use height:480
    45      tag:           match on a tag
    46      width:         use width:min-max to match images having a width of at least min 
    47                     and at most max. Use width:min- to specify only an underbound and
    48                     width:-max to specify only an upperbound.
    49                     Exact matches should use width:640
    50      childrenof:    Find child permanodes of a parent permanode (or prefix
    51                     of a parent permanode): childrenof:sha1-527cf12