它是一个元异步变量。

“Foo”的定义有很多含义:

bar, and baz are often compounded together to make such words as foobar, barbaz, and foobaz. www.nationmaster.com/encyclopedia/Metasyntactic-variable Major concepts in CML, usually mapped directly onto XMLElements (to be discussed later). wwmm.ch.cam.ac.uk/blogs/cml/ Measurement of the total quantity of pasture in a paddock, expressed in kilograms of pasture dry matter per hectare (kg DM/ha) www.lifetimewool.com.au/glossary.aspx Forward Observation Officer. An artillery officer who remained with infantry and tank battalions to set up observation posts in the front lines from which to observe enemy positions and radio the coordinates of targets to the guns further in the rear. members.fortunecity.com/lniven/definition.htm is the first metasyntactic variable commonly used. It is sometimes combined with bar to make foobar. This suggests that foo may have originated with the World War II slang term fubar, as an acronym for fucked/fouled up beyond all recognition, although the Jargon File makes a pretty good case ... explanation-guide.info/meaning/Metasyntactic-variable.html Foo is a metasyntactic variable used heavily in computer science to represent concepts abstractly and can be used to represent any part of a ... en.wikipedia.org/wiki/FOo Foo is the world of dreams (no its not) in Obert Skye's Leven Thumps series. Although it has many original inhabitants, most of its current dwellers are from Reality, and are known as nits. ... en.wikipedia.org/wiki/Foo (place) Also foo’. Representation of fool (foolish person), in a Mr. T accent en.wiktionary.org/wiki/foo

资源:谷歌

在我的同事中，术语“foo”的含义(或者更准确地说是使用)是作为一个占位符来代表一个名称的示例。例子包括，但不限于，yourVariableName, youobjectname，或yourColumnName。

今天，由于几个原因，我避免使用“foo”，而更喜欢使用这种类型的命名替换。

在我早年的时候，我最初发现在任何例子中使用“foo”作为一个位置来表示f' up的东西是令人困惑的。我想要一个实际的例子，而不是一些无聊的东西。 你的结果可能会有所不同，但我总是，100%，每次，从来没有失败，得到更多关于使用“foo”的实际变量的含义的后续问题。

它是一个元异步变量。

In my opinion every programmer has his or her own "words" that is used every time you need an arbitrary word when programming. For some people it's the first words from a childs song, for other it's names and for other its something completely different. Now for the programmer community there are these "words" as well, and these words are 'foo' and 'bar'. The use of this is that if you have to communicate publicly about programming you don't have to say that you would use arbitratry words, you would simply write 'foo' or 'bar' and every programmer knows that this is just arbitrary words.

Foo用作占位符名称，通常在示例代码中表示所命名的对象或名称的选择不是示例的关键部分。Foo后面通常跟着bar、baz，如果需要多个这样的名称，甚至还有bundy。维基百科称这些名称为元异步变量。Python程序员应该使用spam, eggs, ham，而不是foo等。

foo在SA中有很好的用途。

我也见过程序员在想不出一个有意义的名字(比如tmp的替代品)时使用foo，但我认为这是对foo的误用。