Text highlighting method in a text processing system

Description

[0001] This invention relates to a text highlighting method in a text processing system and more particularly to a method for the highlighting of a block of characters for deletion, moving or copying.

[0002] Heretofore text processing machines included hardware and controls that enabled an operator to highlight on a display screen a character or a block of characters in thetext stored in the machine. One or more selected functions may then be applied to the character(s) within this block. Typically, such functions include the deletion, movement or copying of the highlighted character(s) contained within the block. However, the controls limited the operator to start the character highlighting definition by positioning a cursor at a starting point nearest the start of the character or characters to be highlighted and subsequently positioning the cursor to end the block definition at an end point nearest the end of the identified characters. This restriction reduces the productivity of the operator by placing an artificial constraint on the manner in which the operator defines the character or block of characters to be highlighted.

[0003] Thus, German patent application DE_-A1--2 606 491 describes a text processing system in which a memory stores the addresses assigned to the limits of the text to be highlighted. After depressing a function key assigned to a processing command, the memory stores the address assigned to the limit indicating the start position marked by the cursor. Then the cursor is moved to the limit indicating the area end. At the same time, the area between the limits is optically outlined, for example by flashing.

[0004] The present invention is therefore a method for highlighting a block of characters on a display of a text processing system previously to process a function of delete, move or copy, the text processing system including a keyboard, a text storage buffer for storing characters entered by an operator on a keyboard and a text storage buffer control defining first and second location pointers and a cursor for indicating individual characters in the text storage buffer. The method consists in initially positioning the cursor on the display for defining the first location pointer at one of the characters and subsequently positioning the cursor for defining the second location pointer to indicate another character, the position of the second location pointer on the display being independent of the position of the first location pointer; then determining which character identified by the location pointers appears earliest in the text and identifying this character by a start pointer and identifying the latter character by an end pointer so that the operator may define the characters bounding the block to be highlighted in any sequence desired; and then highlighting the block of characters stored in the text storage buffer between a character identified by the start pointer and a character identified by the end pointer.

[0005] A more complete understanding of the invention may be had by reference to the following detailed description when taken in conjunction with the accompanying drawings, wherein:

Figure 1 is a block diagram of various components in a text processing system in which the present invention is employed;

Figure 2 is a block diagram of logic element components in the processor illustrated in Figure 1;

Figure 3 is a logic flow chart of the block definition routine forming a portion of the present invention;

Figure 4 is a logic flow chart for a cursor up or down motion routine forming a portion of the present invention;

Figure 5 is a logic flow chart of a cursor movement routine for movement other than up and down; and

Figure 6 is a logic flow chart of the highlight routine forming a portion of the present invention.

[0006] Referring now to the drawings, wherein like reference characters designate like or corresponding parts throughout several views, Figure 1 illustrates a text processing system 10 which prepares hard or printed copies of text entered by operator controlled keys on the keyboard 12. The keyboard 12 drives a processor 14. The processor 14 is operably interconnected to a visual display 16, a diskette drive 18 and a random access memory 20 by a memory bus 22. A system clock 23 is provided for timing functions within the text processing system 10. Text is input to the system by an operator entering keystrokes on the keyboard 12, 'which includes a conventional typewriter keyboard with additional control keys. The text input by the operator appears as a textual display on the display screen 16 and the keystroke and instruction data is placed into a memory for future recovery in preparing hard copy.

[0007] One important control function in keyboard 12 is the definition or highlighting of a character or a block or group of sequential characters in the text stored in memory and displayed on display screen 16. Once a block of characters is defined, a number of functions are available for performance on this block. For example, the character or characters in the block may be deleted, moved to another part of the text in the memory, or copied at another location in the text. The present invention permits the operator to define the block by moving a cursor or other indication pointer either forward or backward in the text. This allows the operator to define the block in whichever direction is easiest, rather than placing an artificial constraint on the direction of cursor motion as required in previous systems. The text processing machine 10 then functions to highlight the character or characters within the block in preparation for a further function.

[0008] Referring to Figure 2, the processor 14 is further detailed to show typical logic hardware elements as found in such processors. The processor may be a commercially available unit, such as from Intel Corporation and identified by the Number 8086. Typically, the processor includes a control logic unit 30 which responds to interrupts on a device bus 21 from the keyboard 12. The control logic unit 30 is also connected to the data and address bus 34 interconnected to various other logic units of the processor 14.

[0009] In response to a fetch instruction from the random access memory 20, the control logic unit 30 generates control signals to other logic elements of the processor. These control signals are interconnected to the various other elements by means of a control line 36 which is illustrated directly connected to an arithmetic logic unit 38 and identified as a "control" line 36 to other elements of the processor. Synchronous operation of the control unit 30 with other logic elements of the processor 14 is achieved by means of clock pulses input to the processor from an external clock source 40. This instruction bus is also shown interconnected to other logic elements of the processor detailed in Figure 2.

[0010] Data and instructions to be processed in the processor 14 are input through a bus control logic unit 42. Data to be processed may also come from program input/output control logic 44. The bus control logic 42 connects storage elements of the memory 20 and receives instructions for processing data received from the data input/output control 44 or received from the random access memory 20. Thus, the input/ output control 44 receives data from the keyboard 12 or the memory 20 while the bus control logic 42 receives instructions and/or data from the same memory. Note that different storage sections of the random access memory are identifiable for instruction storage and data storage.

[0011] Device control information from the processor 14 is output through the program input/output controller 44 over a data bus (48, 49). Input data on the data bus (48, 49) from the keyboard 12 is processed internally through the processor by instructions on the bus 34 to the scratch register 52. The arithmetic logic unit 38, in response to a control signal on line 36 and in accordance with instructions received on the memory bus 22, performs arithmetic computations which may be stored in temporary scratch registers 52. Various other transfers of data between the arithmetic logic unit 38 and other logic elements of the processor are of course possible. Such additional transfers may be to a status register 60, data pointer register 56 or a stack pointer register 58. Also in the data stream for these various logic elements by means of the bus 34 is a program counter 54.

[0012] A particular operating sequence for the processor 14 is determined by instructions and data on the memory bus 22 and input data on the bi-directional bus (48, 49). As an example, in response to received instructions, the processor transfers data stored in the scratch registers 52 to one of the registers 56, 58 or 60. Such operations of processors as detailed in Figure 2 are considered to be well known and understood by one of ordinary skill in the data processing field. A detailed description of each operation of the processor of Figure 2 for the described invention would be useless to an understanding of the invention as claimed.

[0013] With reference again to Figure 1, the operator keystrokes are displayed on display screen 16 quite similar in nature to a conventional television receiver screen. This screen either displays a full page of text, a partial page or in some systems, only a single line of text. The display not only provides a visual presentation to the operator of the text being prepared but also provides prompting instructions for the operator on how to interface with the machine.

[0014] The diskette drive 18 includes a magnetic disk for maintaining keystroke and instruction data in a semi-permanent manner in association with the text storage buffer (TSB) 74 as a part to the random access memory 20 discussed hereinafter. Typically, parts of a single page of text or a complete page of text in a document stored in the text processing system 10 is stored in the text storage buffer while the remaining document is stored in the diskette drive.

[0015] The random access memory 20 represents a combination of electronic hardware and software to perform a number of discrete functions within the text processing system 10. The keystroke control service function 70 takes a keystroke from the keyboard 12 and determines which of the keystroke service routines 72 is to be used to process the keystroke. A routine may be found in keystroke service routines 72 to service every keystroke on the keyboard 12. if the keystroke represents a typed character for insertion in a text, a routine in keystroke service routines 72 will insert the keystroke in the data stream within the text storage buffer (TSB) 74 for display and eventual hard copy. Also within the keystroke service routines 72 are the block definition routine 76 (Figure 3) and the highlight routine 100 (Figure 6). These routines act to define a block of characters and perform the desired highlighting function on that block.

[0016] The text storage buffer (TSB) 74 stores the text being displayed on the display screen 16. Routines are provided for handling and updating the text stored therein within a TSB control block 75. A display access method program 80 controls the formatting of text on the display screen 16 through display refresh buffer 82.

[0017] The text stored in the TSB 74 is in contextual array. In other words, the characters and the controls that format the characters in the text are stored in sequential order from the beginning to the end of the text. The information on display screen 16, in turn, is displayed in a spatial array, i.e., each graphic to be displayed is displayed at some spatial (X, Y) coordinate relative to the top left hand corner of the display 16. Therefore, to define a block of characters in both TSB 74 and on the display screen 16, a bi-directional character definition routine is stored as one of the keystroke service routines. A routine is provided in memory 20 for converting the contextual array to the spatial array for interaction between the TSB 74 and the display 16 to permit the bi-directional character definition.

[0018] One portion of the TSB control block 75 comprises a set of pointers which identify characters in the text stored in the TSB 74. The TSB manager 84 will be instructed by a keystroke service routine to set the first location pointer LOC PTR 1 to identify a preselected character in the TSB. The TSB manager 84 will also set the second location pointer LOC PTR 2 to a preselected character stored in the TSB 74 upon direction by the keystroke service routine. Whenever text is moved or altered within the text storage buffer, the location pointers will always indicate the preselected characters as long as the characters remain in the memory of the text processing system 10. The location pointers will indicate the preselected characters even if they have moved out of the TSB 74 and into the diskette drive 18 for storage. Typically, as noted above, the TSB 74 will store a portion of or one entire page of text in a given document stored within the text processing system 10. The remainder of the document will be stored on magnetic disks in the diskette drive 18. The location pointers will also indicate whether the preselected characters are on that page or stored in the diskette drive 18. If stored in the diskette drive, the location pointers will indicate whether these characters are on a prior or subsequent page.

[0019] The TSB control block 75 also includes a cursor pointer which identifies a character stored in the TSB 74. A cursor key controlled display cursor identifies a character displayed on display screen 16 perceived visually by the operator. The cursor pointer and display cursor identify the identical character substantially continuously during the operation of system 10. The only time at which the indicated characters may not correspond is during an internal operation necessary to service an operator request, for example, the display cursor moving across the line of text displayed. Between the time the operator presses the cursor key and the time when the cursor moves on the display screen, there will be a very short time when the location cursor is not equal to the display cursor because the routines have not had time to execute.

[0020] With reference to Figure 3, the block definition routine 76 is represented by a series of logic sequences. The operator will first press a delete, move or copy key on the keyboard 12 as represented by sequence 90. The keystroke is transferred into the keystroke service routines 72 (KSR) for processing in sequence 92. When the delete, move or copy key is depressed, the position of the display cursor will identify the location of the first location pointer LP1 to identify one end of the character or block of characters to be enlighted. This function is represented by sequence 93. The operator may, depending on the key depressed, then employ either of two modes of highlighting. In one mode ("highlight to cursor" mode) similar to the one described in German patent application DE-Al-2606491 the other end of the block of characters is determined by the location of the display cursor at a given moment. In the second mode ("highlight between pointers" mode), the other end of the block is defined by the second location pointer, regardless of the position of the display cursor.

[0021] The operator activates the "highlight to cursor" mode by depressing a suitable key on the keyboard 12. If this mode is activated, the display cursor forms one boundary of the block and the first location pointer (LP1) is the other, regardless of the other actions of the operator. This activation is represented as sequence 94. The operator can also activate the "highlight between pointers" mode represented by a sequence 96. It should be noted that this mode is truly representative of the invention. In this mode, the operator positions the display cursor to identify the character which the operator desires to be identified by the second location pointer. The operator inputs a keystroke and the second location pointer (LP2) thereafter represents that character and defines the other end of the block of characters. Subsequently, the display cursor may be moved throughout the text without shifting the boundaries of the character block.

[0022] In general, the system 10 uses the "highlight to cursor" mode after the first end of the block of characters has been identified and until the other end of the block has been identified. After both ends have been identified, the system uses the "highlight between pointers" mode until the function has been completed or cancelled.

[0023] Without consideration of the particular mode, the block definition routine 76 disables any other highlights on the display screen 16, as represented by sequence 98. There are spelling functions, spelling check functions and other functions which also employ highlighting of the display screen. The deletion of the other highlighting avoids confusion for the operator because the only thing the operator sees highlighted on the display screen 16 is text to be deleted moved or copied.

[0024] The block definition routine 76 then calls a highlight routine 100 (Figure 1 and 6), as represented by sequence 102. The purpose of the highlight routine is to determine where the beginning and end pointers of the block of text to be highlighted are to be located. This is necessary as the text processing system 10 builds the highlighted text beginning at the top of the display and moves downward in the text. However, in the highlight between pointers, the second location pointer is the second one used in time, but not necessarily in the text. The second pointer location may be prior to the first pointer location in the text, at a corresponding location or be positioned after the first pointer location. In the "highlight to cusor" mode, the display cursor forming the final boundary on the block may, in turn, be positioned before at or after the first location pointer in the text.

[0025] The "BUILD" routine, represented by sequence 99, will be called if necesary to change the page or portion of a page stored in the TSB 74 (Figure 1). Additional keystroke information may be input in the text during highlighting as desired, as represented by sequences 101 and 103. The text processing system 10 awaits the depression of an "enter" key by the operator to determine the location of the location pointer or cursor pointerto fully define the character or block of characters to be highlighted. This function is represented by test 105 (Figure 6). If the highlight function is not active, the routine will disable the display highlight, represented by sequence 106, and return the highlight routine to the routine of Figure 3 at the return call.

[0026] If the highlighting is active, the routine will then determine whether the "highlight to cursor" or "highlight between pointers" mode has been selected by the operator. This determination is represented by a test 108 (Figure 6). If the "highlight between pointers" mode is selected, the routine will then determine if the first location pointer lies beyond the second location pointer in the text as represented by test 110.

[0027] The internal registers of processor 14 maintain a start pointer (SP) and an end pointer (EP) for entry into the display control block 86 (Figure 1) so that at the next energization of the display access method program 80, the text display will be highlighted beginning with the topmost boundary and moving downward in the text. The principle function of highlight routine 100 is to determine which location pointer appears first in the text and make this the start pointer SP. The other location then becomes the end pointer EP.

[0028] If test 110 (Figure 6) is answered yes, i.e., the first location pointer lies beyond the second location pointer in the text, then the first location pointer is the end pointer EP and the second location pointer LP2 is the start pointer SP, as indicated by sequence 112. If the test 110 is answered no, then the second location pointer LP2 is the end pointer EP and the first location pointer LP1 is the start pointer SP as represented by sequence 114.

[0029] Once the starting point and ending point defining the boundary of the block is determined, the highlighting may be enabled to appear on the display screen 16 in most cases. However, while most characters stored in the TSB 74 occupy only one byte of information, some characters, such as control instructions, contain more than one byte per character on the display. To highlight a multiple byte character, the end pointer should indicate the last byte of the sequence of bytes representing that character. However, the operator can only position the display cursor or location pointer at the first byte of a multi-byte character.

[0030] Each multi-byte character is introduced by a sequence byte, a class byte, a count byte and a type byte. The sequence byte indicates the presence of a multi-byte character. The class byte and type byte together tell the machine 10 what type of control is represented by the multi-byte character. For example, an instruction such as a format change or keyboard change may be directed by these bytes. The count byte, which is the second byte of the sequence, indicates how long the sequence is, starting with and including the count byte.

[0031] The highlight routine 100 makes provisions for multi-byte character text controls. The routine determines if the end point EP is on a text control, represented by test 116. If so, the end pointer EP is automatically positioned at the end of the text control character by examining 'the count byte and moving the end pointer the appropriate number of bytes as represented by sequence 117. After sequence 117, or if the end pointer EP is not on a text control, the start pointer SP and end pointer are entered into the display control block 86 and the text is highlighted on the display screen 16 as represented by sequence 119.

[0032] If the "highlight to cursor" mode is selected, the test 108 will be answered yes. In the "highlight to cursor" mode, the highlight routine becomes somewhat more complex because the text stored in the TSB 74 is in a stream of continuous contextual characters while the text displayed on display screen 16 is in a spatial (X, Y) coordinate format. When the operator moves the display cursor up and down the text, the system 10 must translate the motion in the spatial array on the display screen 16 to a contextual array in the TSB 74. This translation is performed by a "MOVE" function. The "MOVE" function permits the cursor pointer within the TSB 74 to indicate the identical character as the display cursor.

[0033] The cursor pointer will be represented by a temporary pointer (TP) during the operation in the "highlight to cursor" mode as represented by sequence 115. If the display cursor is being moved up or down, test 118 will direct the routine to call the "CONSP" routine (convert spatial to contextual) as represented by sequence 120.

[0034] The updated display cursor will update the cursor pointer in the TSB 74 through the "MOVE" function and the new location of the cursor pointer will form a temporary pointer (TP) in sequence 121. When this is done, or if there is no cursor up or down motion, the test 122 will determine- whether the temporary pointer is beyond the first location pointer. If so, the temporary pointer represents the start pointer and the first location pointer represents the end pointer as represented by sequence 124. If the temporary pointer TP is not beyond the first location pointer LP1, the first location pointer forms the start pointer SP and the temporary pointer TP forms the end pointer EP as represented by sequence 126. The start and end pointers may then be entered into the display control block 86 for display on the display screen 16 in a manner similar to the highlight between pointer mode.

[0035] Referring to Figure 4, the cursor up or down motion routine is illustrated by a series of sequences. Activation of the cursor up or down motion by the operator, represented by sequence 130, is processed in the appropriate key stroke service routine KSR represented by sequence 132.

[0036] The routine highlight is called, as indicated by sequence 134, which provides the pointers for highlighting on the display. The "MOVE" routine is called, represented by sequence 136, to update the display cursor and inform the system of the desired location of the cursor pointer in the TSB 74. The routine sets the cursor point in the TSB 74, as represented by sequence 138 before returning to the routine of Figure 6, represented by sequence 140.

[0037] During cursor up or down motion, the display cursor informs the cursor pointer within the TSB 74 of the proper location so that the cursor pointer is synchronous with the display cursor. Referring to Figure 5, a routine for other cursor motion is provided which is represented by a series of sequences. An operator may select a function on keyboard 12 which directs the cursor to go to a particular page of text. The keystroke of such a function is represented by sequence 152. The appropriate keystroke service routine KSR, represented as sequence 154 processes the input keystroke. Internal calculations within the machine determine where the cursor pointer should be located in the TSB 74. Sequence 156 represents the motion of the cursor pointer within the TSB. It is then necessary to update the display cursor with reference to the location of the cursor pointer in the TSB 74. The function then calls the highlight routine, as represented by sequence 158.

[0038] There are two paths that may be taken. If the new cursor pointer location is on the same page of text stored in the TSB 74 but not displayed on display screen 16, the sequence 160 will be answered no. The routine update will be called, as represented by sequence 162, to update the display as it may be necessary to display different portions of the same page as stored in the TSB 74. If the new location of the cursor pointer is on a page prior to or subsequent to the present page stored in the TSB, it will be necessary to move the cursor pointer and build the text within the TSB 74 as represented by sequence 164.

[0039] In summary, the block definition routine permits the operator to begin at either end in defining a character or block of characters to be deleted, moved or copied. This feature enhances the productivity of the operator by defining the block in whichever direction is easiest, rather than placing an artificial constraint on the direction of cursor movement. In addition, depending on the function, the system 10 will activate either the "highlight to cursor" or "highlight between pointers" mode. The "highlight to cursor" mode highlights the characters between the initial point of the cursor and the present position of the cursor. The "highlight between pointers" mode permits the cursor to be moved on the display screen without affecting the block after definition of the block.

Claims

1. Method for highlighting a block of characters on a display (16) of a text processing system (10) previously to process a function such as delete, move or copy, said text processing system also comprising a keyboard (12), a text storage buffer (74) for storing characters entered by an operator on said keyboard, said display (16) displaying; characters stored in said text storage buffer, and a text storage buffer control block (75) for defining at least first and second location pointers (LP1, LP2) for visual displays on said display and for indicating individual characters stored in said text storage buffer corresponding to the position of a cursor on said display;

said method being characterized in that it comprises the following sequence of steps:

- initially positioning said cursor for defining the first location pointer (LP1) at one of the characters and subsequently positioning said cursor for defining the second location pointer (LP2) to indicate another character, the position of the second location pointer (LP2) on said display being independent of the position of the first location pointer (LP1);

then determining which character identified by the location pointers (LP1, LP2) appears earliest in the text and identifying this character by a start pointer (SP) and identifying the latter character by an end pointer (EP) so that the operator may define the characters bounding the block to be highlighted in any sequence desired; and

then highlighting said block of characters stored in said text storage buffer (74) between a character identified by said start pointer (SP) and a character identified by said end pointer (EP), said block of characters remaining highlighted when the cursbr is moved through said block or away from said block.

2. Method according to claim 1 wherein the characters defined by the operator bounding the text to be highlighted are determined by said cursor prior to highlighting the text so that said cursor may be moved through the text without altering the text to be highlighted.

3. Method according to claim 1 or 2 wherein said cursor is defined by a cursor pointer.

4. Method according to any one of claims 1 to 3 wherein any highlighting of text other than that bounded by said start and end pointers (SP, EP) is disabled.

Ansprüche

1. Methode, um einen Zeichenblock auf einem Darstellungsmittel (16) eines Textverarbeitungssystems (10) vor einer Funktion wie Löschen, Übertragen oder Kopieren hervorzuheben, wobei das genannte Textverarbeitungssystem auch eine Tastatur (12) aufweist sowie einen Textzwischenspeicher (74), um von einem Operator mittels der genannten Tastatur eingegebene Zeichen zu speichern, wonach das genannte Darstellungsmittel (16) die im genannten Textzwischenspeicher eingelagerten Zeichen darstellt, und einen Textzwischenspeicher-Steuerblock (75), der zumindest einen ersten und einen zweiten Platzzeiger (LP1, LP2) bildlich auf dem genannten Darstellungsmittel darstellt und einzelne, im genannten Textzwischenspeicher eingelesene Zeichen anzeigt, die der Stellung eines Cursors auf dem genannten Darstellungsmittel entsprechen;

und die genannte Methode dadurch gekennzeichnet ist, dass sie folgende Schrittfolge aufweist:

- anfängliches Positionieren des genannten Cursors, um den ersten Platzpointer (LP1) an einem der Zeichen zu definieren und anschliessend den genannten Cursor zu positionieren, um den zweiten Platzpointer (LP2) zu definieren, der auf ein anderes Zeichen hinweist, wobei die Position des zweiten Platzpointers (LP2) auf dem genannten Darstellungsmittel unabhängig von der des ersten Platzpointers (LP1) ist;

- anschliessende Festlegung desjenigen der von den genannten Platzpointern (LP1, LP2) identifizierten Zeichen, das zuerst im Text erscheinen soll, und Identifizierung dieses Zeichens durch einen Startpointer (SP), sowie Identifizierung des zweiten Zeichens durch einen Endpointer (EP), wodurch es dem Operator möglich wird, die Zeichen zu definieren, die den hervorzuhebenden Block einer beliebigen Folge begrenzen; und

- anschliessendes Hervorheben des im genannten Textzwischenspeicher (74) eingelesenen Zeichenblocks zwischen einem Zeichen, das vom genannten Startpointer (SP) identifiziert wurde, und einem Zeichen, das vom genannten Endpointer (EP) definiert, wurde, wobei der genannte Zeichenblock hervorgehoben bleibt, wenn der Cursor durch den genannten Block bewegt oder davon entfernt wird.

2. Methode nach Anspruch 1, bei der die vom Operator definierten Zeichen, die den hervorzuhebenden Text begrenzen, vor dem Hervorheben des Textes vom genannten Cursor festgelegt werden, so dass dieser Cursor durch den Text bewegt werden kann, ohne den hervorzuhebenden Text zu ändern.

3. Methode nach Anspruch 1 oder 2, bei der der genannte Cursor von einem Cursorpointer definiert wird.

4. Methode nach den Ansprüch 1 bis 3, bei der jedes Hervorheben eines Textes, der nicht durch die genannten Start- und Endpointer (SP, EP) eingegrenzt ist, unterbunden wird.

Revendications

1. Méthode de mise en évidence d'un bloc de caractères sur un tableau d'affichage (16) d'un système de traitement de texte (10) avant le traitement d'une fonction telle que l'effacement, l'entraînement ou la copie, ledit système de traitement de texte comprenant aussi un clavier (12), une mémoire intermédiaire d'emmagasinage de texte (74) pour emmagasiner des caractères entrés audit clavier par un opérateur, ledit tableau d'affichage (16) affichant des caractères emmagasinés dans ladite mémoire intermédiaire d'emmagasinage de texte, et un bloc de commande de mémoire intermédiaire d'emmagasinage de texte (75) pour définir au moins des premier et second pointeurs d'emplacement (LP1, LP2) pour l'affichage visuel sur ledit tableau d'affichage et pour indiquer des caractères individuels emmagasinés dans ladite mémoire intermédiaire d'emmagasinage de texte correspondant à la position d'un curseur sur ledit tableau d'affichage,

ladite méthode étant caractérisée en ce qu'elle comprend la séquence suivante d'étapes:

- le positionnement initial dudit curseur pour définir le premier pointeur d'emplacement (LP1 ) à l'un des caractères et ensuite le positionnement dudit curseur pour définir le second pointeur d'emplacement (LP2) pour indiquer un autre caractère, la position du second pointeur d'emplacement (LP2) sur ledit tableau d'affichage étant indépendante de la position du premier pointeur d'emplacement (LP1),

puis la détermination du caractère identifié par les pointeurs d'emplacement (LP1, LP2) qui apparaît le premier dans le texte et l'identification de ce caractère par un pointeur de début (SP) et l'identification du dernier caractère par un pointeur de fin (EP) si bien que l'opérateur peut définir les caractères limitant le bloc à mettre en évidence dans n'importe quelle séquence désirée, et

alors la mise en évidence dudit bloc de caractères emmagasiné dans ladite mémoire intermédiaire d'emmagasinage de texte (74) entre un caractère identifié par ladit pointeur de début (SP) et un caractère identifié par ledit pointeur de fin (EP), ledit bloc de caractères restant mis en évidence lorsque le curseur est déplacé dans ledit bloc ou éloigné de celui ci.

2. Méthode selon la revendication 1 dans laquelle les caractères définis par l'opérateur comme limitant le texte à mettre en évidence, sont déterminés par ledit curseur avant de mettre le texte en évidence si bien que ledit curseur peut être déplacé dans le texte sans modifier de texte à mettre en évidence.

3. Méthode selon la revendication 1 ou 2 dans laquelle ledit curseur est défini par un pointeur de curseur.

4. Méthode selon l'une quelconque des revendications 1 à 3 dans laquelle toute mise en évidence de texte autre que celui limité par lesdites pointeurs de début et de fin (SP, EP), est déconditionnée.

Drawing