Eddie > Block functions/Tools > Open Search & replace window Index

(Joker expansion)

Only in the full version of Eddie:

In search-texts with multiple jokers in particular it is important to know in which order and under what circumstances the jokers are expanded. Expansion in this context means the portion of the text region that the joker encompasses to achieve a match between the search-text and the main text. During the search Eddie proceeds as follows:

• The search-text is analysed and split up into its constituent parts. During this Eddie differentiates between fixed text data and jokers. The search-text consists of n fixed text portions that are separated by n-1 jokers (n is greater or equal to 1; an empty search-text never matches).
• Eddie now goes through the text forwards character by character and each time compares the search-text with the main text at the current position. When the end of the text is reached the search is completed. A match between search-text and the main text triggers the desired action (replacement, marking) and with Search/replace global will carry on to the next matching part of the text.

The comparison between the search-text and the current position in the main text looks like this:

• Eddie starts with the first fixed text portion of the search-text. If its contents differs from the main text, then the comparison will be terminated. There is no match.
• If no jokers are present, then the complete search-text has been gone through already. The comparison will be terminated, the contents of the search and main texts are identical.
• If a joker is present, then it will be set first to its preferred size. This means: With a joker to be held as small as possible the number of characters set in Minimum: ... characters will be jumped over at the current text positon. A joker that is to encompass as many characters as possible will be expanded as far as it can, where the value set in Maximum: ... characters will represent the upper limit.

Now it may happen that certain circumstances will arrest the expansion of the joker. Apart from reaching the end of the text, this is generally due to encountering a character that was not selected in the joker dialog and therefore may not be included in the joker. This sets a limit to the expansion of the joker. If the minimum number of characters cannot be achieved due to this, then the comparison fails and will be terminated.

As soon as the text portion encompassed by the first joker has been established, the characters following it will be compared with the second fixed text portion of the search-text. If the two texts do not match then Eddie alters the size of the joker (downwards or upwards, depending on the setting chosen) and repeats the comparison. This process is repeated until the second part of the search-text either matches or the joker can not be changed further in size due to the parameters assigned to it.

In the case of a match the steps described last (find start region of the joker – compare the next text portion and possibly alter the size of the joker) will be repeated for each further fixed text part. If the comparison fails during this because a joker can not be varied further in its size, the editor returns to the last still alterable joker and attempts a comparison from this position anew. If none of the jokers is expandable any more, then the comparison as a whole will be terminated.

If two or more jokers lie between two text parts, they will be always expanded from left to right. This means that Eddie first attempts to obtain a match by adapting the first joker. If the first one can not be altered further, then it is the turn of the second joker etc.

For jokers with identical names Eddie also checks whethere the referenced text regions have the same contents.