Many improvements to Ledger's Python bindings

1 files changed, 120 insertions, 0 deletions

diff --git a/python/demo.py b/python/demo.py
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+++ b/python/demo.py
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+import sys
+
+import ledger
+
+print "Welcome to the Ledger.Python demo!"
+
+def assertEqual(pat, candidate):
+    if pat != candidate:
+        print "FAILED: %s != %s" % (pat, candidate)
+        sys.exit(1)
+
+# COMMODITIES
+
+pool = ledger.commodity_pool
+
+usd = pool.find_or_create('$')
+eur = pool.find_or_create('EUR')
+xcd = pool.find_or_create('XCD')
+
+assertEqual('$', usd.symbol)
+assertEqual('$', pool['$'].symbol)
+
+assert not pool.find('CAD')
+assert not pool.has_key('CAD')
+assert not 'CAD' in pool
+
+# There are a few built-in commodities: null, %, h, m and s
+assertEqual([u'', u'$', u'%', u'EUR', u'XCD',
+             u'h', u'm', u's'], sorted(pool.keys()))
+
+for symbol in pool.iterkeys(): pass
+for commodity in pool.itervalues(): pass
+
+# jww (2009-11-19): Not working: missing conversion from std::pair
+#for symbol, commodity in pool.iteritems(): pass
+#for symbol, commodity in pool: pass
+
+# This creates a price exchange entry, trading EUR for $0.77 each at the
+# current time.
+pool.exchange(eur, ledger.Amount('$0.77'))
+
+# AMOUNTS & BALANCES
+
+# When two amounts are multipied or divided, the result carries the commodity
+# of the first term.  So, 1 EUR / $0.77 == roughly 1.2987 EUR
+amt    = ledger.Amount('$100.12')
+market = ((ledger.Amount('1 EUR') / ledger.Amount('$0.77')) * amt)
+
+# An amount's "precision" is a notional thing only.  Since Ledger uses
+# rational numbers throughout, and only renders to decimal form for printing
+# to the user, the meaning of amt.precision should not be relied on as
+# meaningful.  It only controls how much precision unrounded numbers (those
+# for which keep_precision is True, and thus that ignore display_precision)
+# are rendered into strings.  This is the case, btw, for all uncommoditized
+# amounts.
+assert not amt.keep_precision
+assertEqual(2, amt.precision)
+assertEqual(2, amt.display_precision)
+
+assertEqual('$-100.12', str(amt.negated()))  # negate the amount
+assertEqual('$0.01', str(amt.inverted()))    # reverse NUM/DEM
+assertEqual('$100.12', str(amt.rounded()))   # round it to display precision
+assertEqual('$100.12', str(amt.truncated())) # truncate to display precision
+assertEqual('$100.00', str(amt.floored()))   # floor it to nearest integral
+assertEqual(market, amt.value(eur))          # find present market value
+assertEqual('$100.12', str(abs(amt)))        # absolute value
+assertEqual('$100.12', str(amt))             # render to a string
+assertEqual('100.12', amt.quantity_string()) # render quantity to a string
+assertEqual('100.12', str(amt.number()))     # strip away commodity
+assertEqual(1, amt.sign())                   # -1, 0 or 1
+assert amt.is_nonzero()                      # True if display amount nonzero
+assert not amt.is_zero()                     # True if display amount is zero
+assert not amt.is_realzero()                 # True only if value is 0/0
+assert not amt.is_null()                     # True if uninitialized
+
+assertEqual(100.12, amt.to_double())
+assert amt.fits_in_long()
+assertEqual(100, amt.to_long())
+
+amt2 = ledger.Amount('$100.12 {140 EUR}')
+
+assert amt2.has_annotation()
+assertEqual(amt, amt2.strip_annotations(ledger.KeepDetails()))
+
+# jww (2009-11-19): Not working: missing conversion from optional<amount_t>
+#assertEqual(ledger.Amount('20 EUR'), amt.annotation.price)
+
+# VALUES
+
+val = ledger.Value('$100.00')
+
+assert val.is_amount()
+assertEqual('$', val.to_amount().commodity.symbol)
+
+# JOURNALS
+
+#journal.find_account('')
+#journal.find_or_create_account('')
+
+# ACCOUNTS
+
+#account.name
+#account.fullname()
+#account.amount
+#account.total
+
+# TRANSACTIONS
+
+#txn.payee
+
+# POSTINGS
+
+#post.account
+
+# REPORTING
+
+#journal.collect('-M food')
+#journal.collect_accounts('^assets ^liab ^equity')
+
+print 'Demo completed successfully.'