JForthBlocks--Forth說 I,J,K 即非 I,J,K 是名 I,J,K

Jimmy's papa為了讓Jimmy小朋友認認字,收收心,偶而會要他念幾頁金剛經,

經中須菩提有云

【 世尊說：我見、人見、眾生見、壽者見， “Because (when) the Tathagata speaks of the view of an ego, a Personality, a being and a life, 即非我見、人見、眾生見、壽者見，是名我見、人見、眾生見、壽者見 “it is not really, (but) is (expediently) called the view of an ego, a personality a being and a life.” 】。

雖然不甚了解此段經文的意義,反正是經典,小朋友有唸有保佑(BoBee)啦!!

不過今天寫Forth小範例時,使用Loop Index卻遇見非預期的結果,讓Jimmy's papa見識到了

Forth說 I,J,K 即非 I,J,K 是名 I,J,K

寫慣一般程式語言的人,或許看了書上的Forth程式碼會主觀認定I是最內迴圈索引,J是外迴圈索引,K是外外迴圈索引

不過事實上Forth的I,J,K是指返回堆疊(Return Stack)當下時間點實際暫存的迴圈體索引, 所以光看程式會以為外外迴圈的索引值要用K,但實際執行取索引值時,返回堆疊(Return Stack)或許只有外外迴圈一個迴圈體而已 ,所以只能用I取索引值

寄件者 scratchlab02

寄件者 scratchlab02

底下是XML,直接貼到XML編輯區,便能自動載入積木程式

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