LibrePCB Developers Documentation
AttributeSubstitutor Class Referencefinal

The AttributeSubstitutor class substitutes attribute keys in strings with their actual values (e.g. replace "{{NAME}}" by "U42", a component's name) More...

#include <attributesubstitutor.h>

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Public Types

using LookupFunction = std::function< QString(const QString &)>
 
using FilterFunction = std::function< QString(const QString &)>
 

Public Member Functions

 AttributeSubstitutor ()=delete
 
 AttributeSubstitutor (const AttributeSubstitutor &other)=delete
 
AttributeSubstitutoroperator= (const AttributeSubstitutor &rhs)=delete
 
 ~AttributeSubstitutor ()=delete
 

Static Public Member Functions

static QString substitute (QString str, LookupFunction lookup=nullptr, FilterFunction filter=nullptr) noexcept
 Substitute all attribute keys in a string with their attribute values. More...
 

Static Private Member Functions

static bool searchVariablesInText (const QString &text, int startPos, int &pos, int &length, QStringList &keys) noexcept
 Search the next variables (e.g. "{{KEY or FALLBACK}}") in a given text. More...
 
static void applyFilter (QString &str, int &start, int &end, FilterFunction filter) noexcept
 
static bool getValueOfKey (const QString &key, QString &value, LookupFunction lookup) noexcept
 

Detailed Description

The AttributeSubstitutor class substitutes attribute keys in strings with their actual values (e.g. replace "{{NAME}}" by "U42", a component's name)

Please read the documentation about the Attributes System to get an idea how the Attributes System works in detail.

See also
librepcb::ProjectAttributeLookup
Attributes System
Todo:

Fix side-effect of the endless loop detection ("{{FOO}} {{FOO}}" is currently substituted by "{{FOO}} " because of the endless loop detection, even if there is actually no endless loop).

Properly implement multiple key substitution ("{{FOO or BAR}}" is currently substituted by "{{FOO}}", even if the attribute {{FOO}} indirectly evaluates to an empty string).

Member Typedef Documentation

◆ LookupFunction

using LookupFunction = std::function<QString(const QString&)>

◆ FilterFunction

using FilterFunction = std::function<QString(const QString&)>

Constructor & Destructor Documentation

◆ AttributeSubstitutor() [1/2]

◆ AttributeSubstitutor() [2/2]

AttributeSubstitutor ( const AttributeSubstitutor other)
delete

◆ ~AttributeSubstitutor()

~AttributeSubstitutor ( )
delete

Member Function Documentation

◆ operator=()

AttributeSubstitutor & operator= ( const AttributeSubstitutor rhs)
delete

◆ substitute()

QString substitute ( QString  str,
LookupFunction  lookup = nullptr,
FilterFunction  filter = nullptr 
)
staticnoexcept

Substitute all attribute keys in a string with their attribute values.

Parameters
strA string which can contain variables ("{{NAME}}"). The attributes will be substituted directly in this string.
lookupThe attribute lookup function (key -> value).
filterIf a function is passed here, the substituted values will be passed to this function first. This allows for example to remove invalid characters if the resulting string is used for a file path.
Returns
True if str was modified in some way, false if not
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◆ searchVariablesInText()

bool searchVariablesInText ( const QString &  text,
int  startPos,
int &  pos,
int &  length,
QStringList &  keys 
)
staticprivatenoexcept

Search the next variables (e.g. "{{KEY or FALLBACK}}") in a given text.

Parameters
textA text which can contain variables
startPosThe search start index (use 0 to search in the whole text)
posThe index of the next variable in the specified text (index of the first '{' character, or -1 if no variable found) will be written into this variable.
lengthIf a variable is found, the length (incl. '{{}}') will be written into this variable.
keysThe variable key names (text between '{{' and '}}', split by ' or ')
Returns
true if a variable is found, false if not
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◆ applyFilter()

void applyFilter ( QString &  str,
int &  start,
int &  end,
FilterFunction  filter 
)
staticprivatenoexcept

◆ getValueOfKey()

bool getValueOfKey ( const QString &  key,
QString &  value,
LookupFunction  lookup 
)
staticprivatenoexcept

The documentation for this class was generated from the following files: