GY-63_MS5611/libraries/LineFormatter/README.md

LineFormatter

Arduino library to enhance the layout of tabular data on serial output,

Description

LineFormatter is a wrapper class for Serial (and other streams) to enhance layout of tabular data.

The class intercepts the TAB (\t) characters printed and replaces them with spaces to the next defined tab-position. These positions can be created with addTab(pos) for absolute positions and addRelTab(n) for relative positions.

Absolute tab positions must be added in increasing order as the class does not check or sort the input. Adding the same tab position is not possible since 0.2.0. Also position 0 will be ignored as tabStop.

The maximum number of tabs is defined by MAX_TAB_STOPS == 12 default. This value can be overruled by -D compile flag or edited in the LineFormatter.h file.

All tab positions can be cleared in one call by clearTabs(). Since 0.2.0 the library also supports removeTab(pos) to remove a single tab.

The function autoNewLine(n) prints a newline after every n lines automatically. This makes it easier to count the lines in a table, e.g after every 10 lines. Setting n to 0 disables this function.

The function gotoPos(pos) prints spaces until the cursor is on position pos. If the current position is beyond pos, it does nothing (check the returned position!). Besides for tabular data, this function can be used to make simple text based graphs, e.g. a sine wave.

The function repeat(n, s, nl) which repeats a character or a string n times. This is followed by nl newlines which is zero by default. repeat() is useful to make separator lines or to print several newlines at once. A simple histogram is easy to make.

The function setMaxLength(n) to cut off (brute force, no intelligence) lines after n characters by injecting an extra newline. This prevents scrolling hundreds of positions to the right. Setting the value to 0 results in no maximum line length.

Note: the maximum line length is 255 as all internal positions are 8 bit. A 16 bit lineFormatter is planned for future (on request).

Interface

#include "LineFormatter.h"

Constructor

• LineFormatter(Print* stream = &Serial) constructor. Connects to a stream, default Serial.
• reset() reset internal variables to restart from default again.

Printing

• size_t write(uint8_t c) implements printing per character.
• uint8_t gotoPos(uint8_t pos) if position is smaller than pos, move to the right. Returns the updated position.
• void repeat(uint8_t n, char c, uint8_t newLine = 0) repeat a char n times. Typical used to create separation lines, or multiple line feeds. The repeated string is optionally followed by a number of newlines.
• void repeat(uint8_t n, const char* str, uint8_t newLine = 0) repeat a "string" n times. The repeated string is optionally followed by a number of newlines. Typical used to create separation lines.

Tab configuration

• bool addTab(uint8_t n) Add a tab at an absolute position. Returns true on success. Note: no tab can be set on position 0 (return false) Note: existing tabs will be ignored (return false)
• bool addRelTab(uint8_t n) Add a tab at a relative position. Returns true on success.
• void clearTabs() remove all the tabs.
• bool removeTab(uint8_t pos) remove a tab at given position. Returns true if a tab exists at the position pos. Returns false if no tab existed.
• void tab(uint8_t n = 1) print zero or more tabs, similar as e.g. "\t\t\t".

Note: Removing a tab is non-reversible (for now), so one cannot insert a removed tab stop again. Also replacing a tab can only be done by clear all the tabs and reinsert the new ones.

Line configuration

• void setMaxLength(uint8_t maxPos) set the maximum line length - bold cut off. Will be disabled when set to 0. Note: maximum line length == 255.
• uint8_t getMaxLength() return max line length set.
• void setAutoNewLine(uint8_t n = 1) n = 0 switches autoNewLine off.
• uint8_t getAutoNewLine() returns number of newlines set before.

Miscellaneous

For debugging and other purposes there are the following functions:

• uint8_t getPos() returns current position.
• void resetLineCount() sets internal lineCounter to zero.
• uint32_t getLineCount() returns current line number (since last reset).
• uint8_t getTabCount() get the number of tab positions.
• uint8_t getTabStop(uint8_t n) returns the position of the n-th tab.
• void printRuler(uint8_t length) prints a dotted line with 5 and 10 markers, and # for tab positions. Line is length long.

Future

Must

• redo documentation misc/debug part

Should

• add sorting to addTab() 0.3.0?
  • insert sort - bit like in removeTab()
  • would allow dynamic inserting.
• add examples
• investigate correct working of maxPosition handling.
• investigate position 1 as tabStop?
  • 0 is ignored but 1 is ambiguous

Could

• 0.3.0 ?
  • addTab ==> addAbsoluteTab()
  • addRelTab ==> addRelativeTab()
  • error handling in addTab()?
• lineFormatter16
  • or just make it 16 bit version to allow tables more than 255 chars wide
  • uses more memory!
  • separate class as 8 bit is everywhere
• right alignment for numbers
• point alignment for floats
• investigate macros again.
• filter for unprintable characters,
  • isAscii() test
  • define replace char, default point?

Wont

• check if print interface is completely covered.
  • due to tab parsing it is, so no speed up.