code: function() {
                  this.aliases.blockHelperMissing = 'helpers.blockHelperMissing';
  
                  // We're being a bit cheeky and reusing the options value from the prior exec
                  var params = [this.contextName(0)];
                  this.setupParams('', 0, params, true);
  
                  this.flushInline();
  
                  var current = this.topStack();
                  params.splice(1, 0, current);
  
                  this.pushSource("if (!" + this.lastHelper + ") { " + current + " = blockHelperMissing.call(" + params.join(", ") + "); }");
              }
docs: [ambiguousBlockValue]  On stack, before: hash, inverse, program, value Compiler value, before: lastHelper=value of last found helper, if any On stack, after, if no lastHelper: same as [blockValue] On stack, after, if lastHelper: value