It says if I want to get the length of a segment, going to pass in that instance, it says from that instance, get the start point, that's the thing I just found.

它的意思是如果我想要,得到一个线段的长度，首先要把这个实例传进来，然后对于这个实例，从开始点，取得x坐标，然后通过同样的操作。

麻省理工公开课 - 计算机科学及编程导论课程节选

Warrington made an encouraging start to the second half with Rob Parker hauled down just short of the line by Stephen Wild, but seconds later Jensen gathered Mark Gleeson's pass and went the length the pitch to score.

BBC: Warrington 22-34 Huddersfield

Not only did Quins fail to take advantage, it was 12-man Wigan who scored again eight minutes into the second half when winger Goulding stole a loose pass and raced the length of the field to touch down under the posts for his 18th try of the campaign.

BBC: Harlequins 12-36 Wigan

Parisse intercepted Parks's loose pass and sprinted almost the length of the pitch before passing inside to Canale to dive over.

BBC: Italy 23-20 Scotland